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Diffstat (limited to '')
| -rw-r--r-- | kernel/auditsc.c | 3042 |
1 files changed, 3042 insertions, 0 deletions
diff --git a/kernel/auditsc.c b/kernel/auditsc.c new file mode 100644 index 0000000000..6f0d6fb652 --- /dev/null +++ b/kernel/auditsc.c @@ -0,0 +1,3042 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* auditsc.c -- System-call auditing support + * Handles all system-call specific auditing features. + * + * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina. + * Copyright 2005 Hewlett-Packard Development Company, L.P. + * Copyright (C) 2005, 2006 IBM Corporation + * All Rights Reserved. + * + * Written by Rickard E. (Rik) Faith <faith@redhat.com> + * + * Many of the ideas implemented here are from Stephen C. Tweedie, + * especially the idea of avoiding a copy by using getname. + * + * The method for actual interception of syscall entry and exit (not in + * this file -- see entry.S) is based on a GPL'd patch written by + * okir@suse.de and Copyright 2003 SuSE Linux AG. + * + * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>, + * 2006. + * + * The support of additional filter rules compares (>, <, >=, <=) was + * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005. + * + * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional + * filesystem information. + * + * Subject and object context labeling support added by <danjones@us.ibm.com> + * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/init.h> +#include <asm/types.h> +#include <linux/atomic.h> +#include <linux/fs.h> +#include <linux/namei.h> +#include <linux/mm.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/mount.h> +#include <linux/socket.h> +#include <linux/mqueue.h> +#include <linux/audit.h> +#include <linux/personality.h> +#include <linux/time.h> +#include <linux/netlink.h> +#include <linux/compiler.h> +#include <asm/unistd.h> +#include <linux/security.h> +#include <linux/list.h> +#include <linux/binfmts.h> +#include <linux/highmem.h> +#include <linux/syscalls.h> +#include <asm/syscall.h> +#include <linux/capability.h> +#include <linux/fs_struct.h> +#include <linux/compat.h> +#include <linux/ctype.h> +#include <linux/string.h> +#include <linux/uaccess.h> +#include <linux/fsnotify_backend.h> +#include <uapi/linux/limits.h> +#include <uapi/linux/netfilter/nf_tables.h> +#include <uapi/linux/openat2.h> // struct open_how +#include <uapi/linux/fanotify.h> + +#include "audit.h" + +/* flags stating the success for a syscall */ +#define AUDITSC_INVALID 0 +#define AUDITSC_SUCCESS 1 +#define AUDITSC_FAILURE 2 + +/* no execve audit message should be longer than this (userspace limits), + * see the note near the top of audit_log_execve_info() about this value */ +#define MAX_EXECVE_AUDIT_LEN 7500 + +/* max length to print of cmdline/proctitle value during audit */ +#define MAX_PROCTITLE_AUDIT_LEN 128 + +/* number of audit rules */ +int audit_n_rules; + +/* determines whether we collect data for signals sent */ +int audit_signals; + +struct audit_aux_data { + struct audit_aux_data *next; + int type; +}; + +/* Number of target pids per aux struct. */ +#define AUDIT_AUX_PIDS 16 + +struct audit_aux_data_pids { + struct audit_aux_data d; + pid_t target_pid[AUDIT_AUX_PIDS]; + kuid_t target_auid[AUDIT_AUX_PIDS]; + kuid_t target_uid[AUDIT_AUX_PIDS]; + unsigned int target_sessionid[AUDIT_AUX_PIDS]; + u32 target_sid[AUDIT_AUX_PIDS]; + char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; + int pid_count; +}; + +struct audit_aux_data_bprm_fcaps { + struct audit_aux_data d; + struct audit_cap_data fcap; + unsigned int fcap_ver; + struct audit_cap_data old_pcap; + struct audit_cap_data new_pcap; +}; + +struct audit_tree_refs { + struct audit_tree_refs *next; + struct audit_chunk *c[31]; +}; + +struct audit_nfcfgop_tab { + enum audit_nfcfgop op; + const char *s; +}; + +static const struct audit_nfcfgop_tab audit_nfcfgs[] = { + { AUDIT_XT_OP_REGISTER, "xt_register" }, + { AUDIT_XT_OP_REPLACE, "xt_replace" }, + { AUDIT_XT_OP_UNREGISTER, "xt_unregister" }, + { AUDIT_NFT_OP_TABLE_REGISTER, "nft_register_table" }, + { AUDIT_NFT_OP_TABLE_UNREGISTER, "nft_unregister_table" }, + { AUDIT_NFT_OP_CHAIN_REGISTER, "nft_register_chain" }, + { AUDIT_NFT_OP_CHAIN_UNREGISTER, "nft_unregister_chain" }, + { AUDIT_NFT_OP_RULE_REGISTER, "nft_register_rule" }, + { AUDIT_NFT_OP_RULE_UNREGISTER, "nft_unregister_rule" }, + { AUDIT_NFT_OP_SET_REGISTER, "nft_register_set" }, + { AUDIT_NFT_OP_SET_UNREGISTER, "nft_unregister_set" }, + { AUDIT_NFT_OP_SETELEM_REGISTER, "nft_register_setelem" }, + { AUDIT_NFT_OP_SETELEM_UNREGISTER, "nft_unregister_setelem" }, + { AUDIT_NFT_OP_GEN_REGISTER, "nft_register_gen" }, + { AUDIT_NFT_OP_OBJ_REGISTER, "nft_register_obj" }, + { AUDIT_NFT_OP_OBJ_UNREGISTER, "nft_unregister_obj" }, + { AUDIT_NFT_OP_OBJ_RESET, "nft_reset_obj" }, + { AUDIT_NFT_OP_FLOWTABLE_REGISTER, "nft_register_flowtable" }, + { AUDIT_NFT_OP_FLOWTABLE_UNREGISTER, "nft_unregister_flowtable" }, + { AUDIT_NFT_OP_SETELEM_RESET, "nft_reset_setelem" }, + { AUDIT_NFT_OP_RULE_RESET, "nft_reset_rule" }, + { AUDIT_NFT_OP_INVALID, "nft_invalid" }, +}; + +static int audit_match_perm(struct audit_context *ctx, int mask) +{ + unsigned n; + + if (unlikely(!ctx)) + return 0; + n = ctx->major; + + switch (audit_classify_syscall(ctx->arch, n)) { + case AUDITSC_NATIVE: + if ((mask & AUDIT_PERM_WRITE) && + audit_match_class(AUDIT_CLASS_WRITE, n)) + return 1; + if ((mask & AUDIT_PERM_READ) && + audit_match_class(AUDIT_CLASS_READ, n)) + return 1; + if ((mask & AUDIT_PERM_ATTR) && + audit_match_class(AUDIT_CLASS_CHATTR, n)) + return 1; + return 0; + case AUDITSC_COMPAT: /* 32bit on biarch */ + if ((mask & AUDIT_PERM_WRITE) && + audit_match_class(AUDIT_CLASS_WRITE_32, n)) + return 1; + if ((mask & AUDIT_PERM_READ) && + audit_match_class(AUDIT_CLASS_READ_32, n)) + return 1; + if ((mask & AUDIT_PERM_ATTR) && + audit_match_class(AUDIT_CLASS_CHATTR_32, n)) + return 1; + return 0; + case AUDITSC_OPEN: + return mask & ACC_MODE(ctx->argv[1]); + case AUDITSC_OPENAT: + return mask & ACC_MODE(ctx->argv[2]); + case AUDITSC_SOCKETCALL: + return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); + case AUDITSC_EXECVE: + return mask & AUDIT_PERM_EXEC; + case AUDITSC_OPENAT2: + return mask & ACC_MODE((u32)ctx->openat2.flags); + default: + return 0; + } +} + +static int audit_match_filetype(struct audit_context *ctx, int val) +{ + struct audit_names *n; + umode_t mode = (umode_t)val; + + if (unlikely(!ctx)) + return 0; + + list_for_each_entry(n, &ctx->names_list, list) { + if ((n->ino != AUDIT_INO_UNSET) && + ((n->mode & S_IFMT) == mode)) + return 1; + } + + return 0; +} + +/* + * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; + * ->first_trees points to its beginning, ->trees - to the current end of data. + * ->tree_count is the number of free entries in array pointed to by ->trees. + * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, + * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, + * it's going to remain 1-element for almost any setup) until we free context itself. + * References in it _are_ dropped - at the same time we free/drop aux stuff. + */ + +static void audit_set_auditable(struct audit_context *ctx) +{ + if (!ctx->prio) { + ctx->prio = 1; + ctx->current_state = AUDIT_STATE_RECORD; + } +} + +static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) +{ + struct audit_tree_refs *p = ctx->trees; + int left = ctx->tree_count; + + if (likely(left)) { + p->c[--left] = chunk; + ctx->tree_count = left; + return 1; + } + if (!p) + return 0; + p = p->next; + if (p) { + p->c[30] = chunk; + ctx->trees = p; + ctx->tree_count = 30; + return 1; + } + return 0; +} + +static int grow_tree_refs(struct audit_context *ctx) +{ + struct audit_tree_refs *p = ctx->trees; + + ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); + if (!ctx->trees) { + ctx->trees = p; + return 0; + } + if (p) + p->next = ctx->trees; + else + ctx->first_trees = ctx->trees; + ctx->tree_count = 31; + return 1; +} + +static void unroll_tree_refs(struct audit_context *ctx, + struct audit_tree_refs *p, int count) +{ + struct audit_tree_refs *q; + int n; + + if (!p) { + /* we started with empty chain */ + p = ctx->first_trees; + count = 31; + /* if the very first allocation has failed, nothing to do */ + if (!p) + return; + } + n = count; + for (q = p; q != ctx->trees; q = q->next, n = 31) { + while (n--) { + audit_put_chunk(q->c[n]); + q->c[n] = NULL; + } + } + while (n-- > ctx->tree_count) { + audit_put_chunk(q->c[n]); + q->c[n] = NULL; + } + ctx->trees = p; + ctx->tree_count = count; +} + +static void free_tree_refs(struct audit_context *ctx) +{ + struct audit_tree_refs *p, *q; + + for (p = ctx->first_trees; p; p = q) { + q = p->next; + kfree(p); + } +} + +static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) +{ + struct audit_tree_refs *p; + int n; + + if (!tree) + return 0; + /* full ones */ + for (p = ctx->first_trees; p != ctx->trees; p = p->next) { + for (n = 0; n < 31; n++) + if (audit_tree_match(p->c[n], tree)) + return 1; + } + /* partial */ + if (p) { + for (n = ctx->tree_count; n < 31; n++) + if (audit_tree_match(p->c[n], tree)) + return 1; + } + return 0; +} + +static int audit_compare_uid(kuid_t uid, + struct audit_names *name, + struct audit_field *f, + struct audit_context *ctx) +{ + struct audit_names *n; + int rc; + + if (name) { + rc = audit_uid_comparator(uid, f->op, name->uid); + if (rc) + return rc; + } + + if (ctx) { + list_for_each_entry(n, &ctx->names_list, list) { + rc = audit_uid_comparator(uid, f->op, n->uid); + if (rc) + return rc; + } + } + return 0; +} + +static int audit_compare_gid(kgid_t gid, + struct audit_names *name, + struct audit_field *f, + struct audit_context *ctx) +{ + struct audit_names *n; + int rc; + + if (name) { + rc = audit_gid_comparator(gid, f->op, name->gid); + if (rc) + return rc; + } + + if (ctx) { + list_for_each_entry(n, &ctx->names_list, list) { + rc = audit_gid_comparator(gid, f->op, n->gid); + if (rc) + return rc; + } + } + return 0; +} + +static int audit_field_compare(struct task_struct *tsk, + const struct cred *cred, + struct audit_field *f, + struct audit_context *ctx, + struct audit_names *name) +{ + switch (f->val) { + /* process to file object comparisons */ + case AUDIT_COMPARE_UID_TO_OBJ_UID: + return audit_compare_uid(cred->uid, name, f, ctx); + case AUDIT_COMPARE_GID_TO_OBJ_GID: + return audit_compare_gid(cred->gid, name, f, ctx); + case AUDIT_COMPARE_EUID_TO_OBJ_UID: + return audit_compare_uid(cred->euid, name, f, ctx); + case AUDIT_COMPARE_EGID_TO_OBJ_GID: + return audit_compare_gid(cred->egid, name, f, ctx); + case AUDIT_COMPARE_AUID_TO_OBJ_UID: + return audit_compare_uid(audit_get_loginuid(tsk), name, f, ctx); + case AUDIT_COMPARE_SUID_TO_OBJ_UID: + return audit_compare_uid(cred->suid, name, f, ctx); + case AUDIT_COMPARE_SGID_TO_OBJ_GID: + return audit_compare_gid(cred->sgid, name, f, ctx); + case AUDIT_COMPARE_FSUID_TO_OBJ_UID: + return audit_compare_uid(cred->fsuid, name, f, ctx); + case AUDIT_COMPARE_FSGID_TO_OBJ_GID: + return audit_compare_gid(cred->fsgid, name, f, ctx); + /* uid comparisons */ + case AUDIT_COMPARE_UID_TO_AUID: + return audit_uid_comparator(cred->uid, f->op, + audit_get_loginuid(tsk)); + case AUDIT_COMPARE_UID_TO_EUID: + return audit_uid_comparator(cred->uid, f->op, cred->euid); + case AUDIT_COMPARE_UID_TO_SUID: + return audit_uid_comparator(cred->uid, f->op, cred->suid); + case AUDIT_COMPARE_UID_TO_FSUID: + return audit_uid_comparator(cred->uid, f->op, cred->fsuid); + /* auid comparisons */ + case AUDIT_COMPARE_AUID_TO_EUID: + return audit_uid_comparator(audit_get_loginuid(tsk), f->op, + cred->euid); + case AUDIT_COMPARE_AUID_TO_SUID: + return audit_uid_comparator(audit_get_loginuid(tsk), f->op, + cred->suid); + case AUDIT_COMPARE_AUID_TO_FSUID: + return audit_uid_comparator(audit_get_loginuid(tsk), f->op, + cred->fsuid); + /* euid comparisons */ + case AUDIT_COMPARE_EUID_TO_SUID: + return audit_uid_comparator(cred->euid, f->op, cred->suid); + case AUDIT_COMPARE_EUID_TO_FSUID: + return audit_uid_comparator(cred->euid, f->op, cred->fsuid); + /* suid comparisons */ + case AUDIT_COMPARE_SUID_TO_FSUID: + return audit_uid_comparator(cred->suid, f->op, cred->fsuid); + /* gid comparisons */ + case AUDIT_COMPARE_GID_TO_EGID: + return audit_gid_comparator(cred->gid, f->op, cred->egid); + case AUDIT_COMPARE_GID_TO_SGID: + return audit_gid_comparator(cred->gid, f->op, cred->sgid); + case AUDIT_COMPARE_GID_TO_FSGID: + return audit_gid_comparator(cred->gid, f->op, cred->fsgid); + /* egid comparisons */ + case AUDIT_COMPARE_EGID_TO_SGID: + return audit_gid_comparator(cred->egid, f->op, cred->sgid); + case AUDIT_COMPARE_EGID_TO_FSGID: + return audit_gid_comparator(cred->egid, f->op, cred->fsgid); + /* sgid comparison */ + case AUDIT_COMPARE_SGID_TO_FSGID: + return audit_gid_comparator(cred->sgid, f->op, cred->fsgid); + default: + WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n"); + return 0; + } + return 0; +} + +/* Determine if any context name data matches a rule's watch data */ +/* Compare a task_struct with an audit_rule. Return 1 on match, 0 + * otherwise. + * + * If task_creation is true, this is an explicit indication that we are + * filtering a task rule at task creation time. This and tsk == current are + * the only situations where tsk->cred may be accessed without an rcu read lock. + */ +static int audit_filter_rules(struct task_struct *tsk, + struct audit_krule *rule, + struct audit_context *ctx, + struct audit_names *name, + enum audit_state *state, + bool task_creation) +{ + const struct cred *cred; + int i, need_sid = 1; + u32 sid; + unsigned int sessionid; + + if (ctx && rule->prio <= ctx->prio) + return 0; + + cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); + + for (i = 0; i < rule->field_count; i++) { + struct audit_field *f = &rule->fields[i]; + struct audit_names *n; + int result = 0; + pid_t pid; + + switch (f->type) { + case AUDIT_PID: + pid = task_tgid_nr(tsk); + result = audit_comparator(pid, f->op, f->val); + break; + case AUDIT_PPID: + if (ctx) { + if (!ctx->ppid) + ctx->ppid = task_ppid_nr(tsk); + result = audit_comparator(ctx->ppid, f->op, f->val); + } + break; + case AUDIT_EXE: + result = audit_exe_compare(tsk, rule->exe); + if (f->op == Audit_not_equal) + result = !result; + break; + case AUDIT_UID: + result = audit_uid_comparator(cred->uid, f->op, f->uid); + break; + case AUDIT_EUID: + result = audit_uid_comparator(cred->euid, f->op, f->uid); + break; + case AUDIT_SUID: + result = audit_uid_comparator(cred->suid, f->op, f->uid); + break; + case AUDIT_FSUID: + result = audit_uid_comparator(cred->fsuid, f->op, f->uid); + break; + case AUDIT_GID: + result = audit_gid_comparator(cred->gid, f->op, f->gid); + if (f->op == Audit_equal) { + if (!result) + result = groups_search(cred->group_info, f->gid); + } else if (f->op == Audit_not_equal) { + if (result) + result = !groups_search(cred->group_info, f->gid); + } + break; + case AUDIT_EGID: + result = audit_gid_comparator(cred->egid, f->op, f->gid); + if (f->op == Audit_equal) { + if (!result) + result = groups_search(cred->group_info, f->gid); + } else if (f->op == Audit_not_equal) { + if (result) + result = !groups_search(cred->group_info, f->gid); + } + break; + case AUDIT_SGID: + result = audit_gid_comparator(cred->sgid, f->op, f->gid); + break; + case AUDIT_FSGID: + result = audit_gid_comparator(cred->fsgid, f->op, f->gid); + break; + case AUDIT_SESSIONID: + sessionid = audit_get_sessionid(tsk); + result = audit_comparator(sessionid, f->op, f->val); + break; + case AUDIT_PERS: + result = audit_comparator(tsk->personality, f->op, f->val); + break; + case AUDIT_ARCH: + if (ctx) + result = audit_comparator(ctx->arch, f->op, f->val); + break; + + case AUDIT_EXIT: + if (ctx && ctx->return_valid != AUDITSC_INVALID) + result = audit_comparator(ctx->return_code, f->op, f->val); + break; + case AUDIT_SUCCESS: + if (ctx && ctx->return_valid != AUDITSC_INVALID) { + if (f->val) + result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); + else + result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); + } + break; + case AUDIT_DEVMAJOR: + if (name) { + if (audit_comparator(MAJOR(name->dev), f->op, f->val) || + audit_comparator(MAJOR(name->rdev), f->op, f->val)) + ++result; + } else if (ctx) { + list_for_each_entry(n, &ctx->names_list, list) { + if (audit_comparator(MAJOR(n->dev), f->op, f->val) || + audit_comparator(MAJOR(n->rdev), f->op, f->val)) { + ++result; + break; + } + } + } + break; + case AUDIT_DEVMINOR: + if (name) { + if (audit_comparator(MINOR(name->dev), f->op, f->val) || + audit_comparator(MINOR(name->rdev), f->op, f->val)) + ++result; + } else if (ctx) { + list_for_each_entry(n, &ctx->names_list, list) { + if (audit_comparator(MINOR(n->dev), f->op, f->val) || + audit_comparator(MINOR(n->rdev), f->op, f->val)) { + ++result; + break; + } + } + } + break; + case AUDIT_INODE: + if (name) + result = audit_comparator(name->ino, f->op, f->val); + else if (ctx) { + list_for_each_entry(n, &ctx->names_list, list) { + if (audit_comparator(n->ino, f->op, f->val)) { + ++result; + break; + } + } + } + break; + case AUDIT_OBJ_UID: + if (name) { + result = audit_uid_comparator(name->uid, f->op, f->uid); + } else if (ctx) { + list_for_each_entry(n, &ctx->names_list, list) { + if (audit_uid_comparator(n->uid, f->op, f->uid)) { + ++result; + break; + } + } + } + break; + case AUDIT_OBJ_GID: + if (name) { + result = audit_gid_comparator(name->gid, f->op, f->gid); + } else if (ctx) { + list_for_each_entry(n, &ctx->names_list, list) { + if (audit_gid_comparator(n->gid, f->op, f->gid)) { + ++result; + break; + } + } + } + break; + case AUDIT_WATCH: + if (name) { + result = audit_watch_compare(rule->watch, + name->ino, + name->dev); + if (f->op == Audit_not_equal) + result = !result; + } + break; + case AUDIT_DIR: + if (ctx) { + result = match_tree_refs(ctx, rule->tree); + if (f->op == Audit_not_equal) + result = !result; + } + break; + case AUDIT_LOGINUID: + result = audit_uid_comparator(audit_get_loginuid(tsk), + f->op, f->uid); + break; + case AUDIT_LOGINUID_SET: + result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val); + break; + case AUDIT_SADDR_FAM: + if (ctx && ctx->sockaddr) + result = audit_comparator(ctx->sockaddr->ss_family, + f->op, f->val); + break; + case AUDIT_SUBJ_USER: + case AUDIT_SUBJ_ROLE: + case AUDIT_SUBJ_TYPE: + case AUDIT_SUBJ_SEN: + case AUDIT_SUBJ_CLR: + /* NOTE: this may return negative values indicating + a temporary error. We simply treat this as a + match for now to avoid losing information that + may be wanted. An error message will also be + logged upon error */ + if (f->lsm_rule) { + if (need_sid) { + /* @tsk should always be equal to + * @current with the exception of + * fork()/copy_process() in which case + * the new @tsk creds are still a dup + * of @current's creds so we can still + * use security_current_getsecid_subj() + * here even though it always refs + * @current's creds + */ + security_current_getsecid_subj(&sid); + need_sid = 0; + } + result = security_audit_rule_match(sid, f->type, + f->op, + f->lsm_rule); + } + break; + case AUDIT_OBJ_USER: + case AUDIT_OBJ_ROLE: + case AUDIT_OBJ_TYPE: + case AUDIT_OBJ_LEV_LOW: + case AUDIT_OBJ_LEV_HIGH: + /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR + also applies here */ + if (f->lsm_rule) { + /* Find files that match */ + if (name) { + result = security_audit_rule_match( + name->osid, + f->type, + f->op, + f->lsm_rule); + } else if (ctx) { + list_for_each_entry(n, &ctx->names_list, list) { + if (security_audit_rule_match( + n->osid, + f->type, + f->op, + f->lsm_rule)) { + ++result; + break; + } + } + } + /* Find ipc objects that match */ + if (!ctx || ctx->type != AUDIT_IPC) + break; + if (security_audit_rule_match(ctx->ipc.osid, + f->type, f->op, + f->lsm_rule)) + ++result; + } + break; + case AUDIT_ARG0: + case AUDIT_ARG1: + case AUDIT_ARG2: + case AUDIT_ARG3: + if (ctx) + result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); + break; + case AUDIT_FILTERKEY: + /* ignore this field for filtering */ + result = 1; + break; + case AUDIT_PERM: + result = audit_match_perm(ctx, f->val); + if (f->op == Audit_not_equal) + result = !result; + break; + case AUDIT_FILETYPE: + result = audit_match_filetype(ctx, f->val); + if (f->op == Audit_not_equal) + result = !result; + break; + case AUDIT_FIELD_COMPARE: + result = audit_field_compare(tsk, cred, f, ctx, name); + break; + } + if (!result) + return 0; + } + + if (ctx) { + if (rule->filterkey) { + kfree(ctx->filterkey); + ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); + } + ctx->prio = rule->prio; + } + switch (rule->action) { + case AUDIT_NEVER: + *state = AUDIT_STATE_DISABLED; + break; + case AUDIT_ALWAYS: + *state = AUDIT_STATE_RECORD; + break; + } + return 1; +} + +/* At process creation time, we can determine if system-call auditing is + * completely disabled for this task. Since we only have the task + * structure at this point, we can only check uid and gid. + */ +static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) +{ + struct audit_entry *e; + enum audit_state state; + + rcu_read_lock(); + list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { + if (audit_filter_rules(tsk, &e->rule, NULL, NULL, + &state, true)) { + if (state == AUDIT_STATE_RECORD) + *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); + rcu_read_unlock(); + return state; + } + } + rcu_read_unlock(); + return AUDIT_STATE_BUILD; +} + +static int audit_in_mask(const struct audit_krule *rule, unsigned long val) +{ + int word, bit; + + if (val > 0xffffffff) + return false; + + word = AUDIT_WORD(val); + if (word >= AUDIT_BITMASK_SIZE) + return false; + + bit = AUDIT_BIT(val); + + return rule->mask[word] & bit; +} + +/** + * __audit_filter_op - common filter helper for operations (syscall/uring/etc) + * @tsk: associated task + * @ctx: audit context + * @list: audit filter list + * @name: audit_name (can be NULL) + * @op: current syscall/uring_op + * + * Run the udit filters specified in @list against @tsk using @ctx, + * @name, and @op, as necessary; the caller is responsible for ensuring + * that the call is made while the RCU read lock is held. The @name + * parameter can be NULL, but all others must be specified. + * Returns 1/true if the filter finds a match, 0/false if none are found. + */ +static int __audit_filter_op(struct task_struct *tsk, + struct audit_context *ctx, + struct list_head *list, + struct audit_names *name, + unsigned long op) +{ + struct audit_entry *e; + enum audit_state state; + + list_for_each_entry_rcu(e, list, list) { + if (audit_in_mask(&e->rule, op) && + audit_filter_rules(tsk, &e->rule, ctx, name, + &state, false)) { + ctx->current_state = state; + return 1; + } + } + return 0; +} + +/** + * audit_filter_uring - apply filters to an io_uring operation + * @tsk: associated task + * @ctx: audit context + */ +static void audit_filter_uring(struct task_struct *tsk, + struct audit_context *ctx) +{ + if (auditd_test_task(tsk)) + return; + + rcu_read_lock(); + __audit_filter_op(tsk, ctx, &audit_filter_list[AUDIT_FILTER_URING_EXIT], + NULL, ctx->uring_op); + rcu_read_unlock(); +} + +/* At syscall exit time, this filter is called if the audit_state is + * not low enough that auditing cannot take place, but is also not + * high enough that we already know we have to write an audit record + * (i.e., the state is AUDIT_STATE_BUILD). + */ +static void audit_filter_syscall(struct task_struct *tsk, + struct audit_context *ctx) +{ + if (auditd_test_task(tsk)) + return; + + rcu_read_lock(); + __audit_filter_op(tsk, ctx, &audit_filter_list[AUDIT_FILTER_EXIT], + NULL, ctx->major); + rcu_read_unlock(); +} + +/* + * Given an audit_name check the inode hash table to see if they match. + * Called holding the rcu read lock to protect the use of audit_inode_hash + */ +static int audit_filter_inode_name(struct task_struct *tsk, + struct audit_names *n, + struct audit_context *ctx) +{ + int h = audit_hash_ino((u32)n->ino); + struct list_head *list = &audit_inode_hash[h]; + + return __audit_filter_op(tsk, ctx, list, n, ctx->major); +} + +/* At syscall exit time, this filter is called if any audit_names have been + * collected during syscall processing. We only check rules in sublists at hash + * buckets applicable to the inode numbers in audit_names. + * Regarding audit_state, same rules apply as for audit_filter_syscall(). + */ +void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx) +{ + struct audit_names *n; + + if (auditd_test_task(tsk)) + return; + + rcu_read_lock(); + + list_for_each_entry(n, &ctx->names_list, list) { + if (audit_filter_inode_name(tsk, n, ctx)) + break; + } + rcu_read_unlock(); +} + +static inline void audit_proctitle_free(struct audit_context *context) +{ + kfree(context->proctitle.value); + context->proctitle.value = NULL; + context->proctitle.len = 0; +} + +static inline void audit_free_module(struct audit_context *context) +{ + if (context->type == AUDIT_KERN_MODULE) { + kfree(context->module.name); + context->module.name = NULL; + } +} +static inline void audit_free_names(struct audit_context *context) +{ + struct audit_names *n, *next; + + list_for_each_entry_safe(n, next, &context->names_list, list) { + list_del(&n->list); + if (n->name) + putname(n->name); + if (n->should_free) + kfree(n); + } + context->name_count = 0; + path_put(&context->pwd); + context->pwd.dentry = NULL; + context->pwd.mnt = NULL; +} + +static inline void audit_free_aux(struct audit_context *context) +{ + struct audit_aux_data *aux; + + while ((aux = context->aux)) { + context->aux = aux->next; + kfree(aux); + } + context->aux = NULL; + while ((aux = context->aux_pids)) { + context->aux_pids = aux->next; + kfree(aux); + } + context->aux_pids = NULL; +} + +/** + * audit_reset_context - reset a audit_context structure + * @ctx: the audit_context to reset + * + * All fields in the audit_context will be reset to an initial state, all + * references held by fields will be dropped, and private memory will be + * released. When this function returns the audit_context will be suitable + * for reuse, so long as the passed context is not NULL or a dummy context. + */ +static void audit_reset_context(struct audit_context *ctx) +{ + if (!ctx) + return; + + /* if ctx is non-null, reset the "ctx->context" regardless */ + ctx->context = AUDIT_CTX_UNUSED; + if (ctx->dummy) + return; + + /* + * NOTE: It shouldn't matter in what order we release the fields, so + * release them in the order in which they appear in the struct; + * this gives us some hope of quickly making sure we are + * resetting the audit_context properly. + * + * Other things worth mentioning: + * - we don't reset "dummy" + * - we don't reset "state", we do reset "current_state" + * - we preserve "filterkey" if "state" is AUDIT_STATE_RECORD + * - much of this is likely overkill, but play it safe for now + * - we really need to work on improving the audit_context struct + */ + + ctx->current_state = ctx->state; + ctx->serial = 0; + ctx->major = 0; + ctx->uring_op = 0; + ctx->ctime = (struct timespec64){ .tv_sec = 0, .tv_nsec = 0 }; + memset(ctx->argv, 0, sizeof(ctx->argv)); + ctx->return_code = 0; + ctx->prio = (ctx->state == AUDIT_STATE_RECORD ? ~0ULL : 0); + ctx->return_valid = AUDITSC_INVALID; + audit_free_names(ctx); + if (ctx->state != AUDIT_STATE_RECORD) { + kfree(ctx->filterkey); + ctx->filterkey = NULL; + } + audit_free_aux(ctx); + kfree(ctx->sockaddr); + ctx->sockaddr = NULL; + ctx->sockaddr_len = 0; + ctx->ppid = 0; + ctx->uid = ctx->euid = ctx->suid = ctx->fsuid = KUIDT_INIT(0); + ctx->gid = ctx->egid = ctx->sgid = ctx->fsgid = KGIDT_INIT(0); + ctx->personality = 0; + ctx->arch = 0; + ctx->target_pid = 0; + ctx->target_auid = ctx->target_uid = KUIDT_INIT(0); + ctx->target_sessionid = 0; + ctx->target_sid = 0; + ctx->target_comm[0] = '\0'; + unroll_tree_refs(ctx, NULL, 0); + WARN_ON(!list_empty(&ctx->killed_trees)); + audit_free_module(ctx); + ctx->fds[0] = -1; + ctx->type = 0; /* reset last for audit_free_*() */ +} + +static inline struct audit_context *audit_alloc_context(enum audit_state state) +{ + struct audit_context *context; + + context = kzalloc(sizeof(*context), GFP_KERNEL); + if (!context) + return NULL; + context->context = AUDIT_CTX_UNUSED; + context->state = state; + context->prio = state == AUDIT_STATE_RECORD ? ~0ULL : 0; + INIT_LIST_HEAD(&context->killed_trees); + INIT_LIST_HEAD(&context->names_list); + context->fds[0] = -1; + context->return_valid = AUDITSC_INVALID; + return context; +} + +/** + * audit_alloc - allocate an audit context block for a task + * @tsk: task + * + * Filter on the task information and allocate a per-task audit context + * if necessary. Doing so turns on system call auditing for the + * specified task. This is called from copy_process, so no lock is + * needed. + */ +int audit_alloc(struct task_struct *tsk) +{ + struct audit_context *context; + enum audit_state state; + char *key = NULL; + + if (likely(!audit_ever_enabled)) + return 0; + + state = audit_filter_task(tsk, &key); + if (state == AUDIT_STATE_DISABLED) { + clear_task_syscall_work(tsk, SYSCALL_AUDIT); + return 0; + } + + context = audit_alloc_context(state); + if (!context) { + kfree(key); + audit_log_lost("out of memory in audit_alloc"); + return -ENOMEM; + } + context->filterkey = key; + + audit_set_context(tsk, context); + set_task_syscall_work(tsk, SYSCALL_AUDIT); + return 0; +} + +static inline void audit_free_context(struct audit_context *context) +{ + /* resetting is extra work, but it is likely just noise */ + audit_reset_context(context); + audit_proctitle_free(context); + free_tree_refs(context); + kfree(context->filterkey); + kfree(context); +} + +static int audit_log_pid_context(struct audit_context *context, pid_t pid, + kuid_t auid, kuid_t uid, unsigned int sessionid, + u32 sid, char *comm) +{ + struct audit_buffer *ab; + char *ctx = NULL; + u32 len; + int rc = 0; + + ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); + if (!ab) + return rc; + + audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, + from_kuid(&init_user_ns, auid), + from_kuid(&init_user_ns, uid), sessionid); + if (sid) { + if (security_secid_to_secctx(sid, &ctx, &len)) { + audit_log_format(ab, " obj=(none)"); + rc = 1; + } else { + audit_log_format(ab, " obj=%s", ctx); + security_release_secctx(ctx, len); + } + } + audit_log_format(ab, " ocomm="); + audit_log_untrustedstring(ab, comm); + audit_log_end(ab); + + return rc; +} + +static void audit_log_execve_info(struct audit_context *context, + struct audit_buffer **ab) +{ + long len_max; + long len_rem; + long len_full; + long len_buf; + long len_abuf = 0; + long len_tmp; + bool require_data; + bool encode; + unsigned int iter; + unsigned int arg; + char *buf_head; + char *buf; + const char __user *p = (const char __user *)current->mm->arg_start; + + /* NOTE: this buffer needs to be large enough to hold all the non-arg + * data we put in the audit record for this argument (see the + * code below) ... at this point in time 96 is plenty */ + char abuf[96]; + + /* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the + * current value of 7500 is not as important as the fact that it + * is less than 8k, a setting of 7500 gives us plenty of wiggle + * room if we go over a little bit in the logging below */ + WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500); + len_max = MAX_EXECVE_AUDIT_LEN; + + /* scratch buffer to hold the userspace args */ + buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); + if (!buf_head) { + audit_panic("out of memory for argv string"); + return; + } + buf = buf_head; + + audit_log_format(*ab, "argc=%d", context->execve.argc); + + len_rem = len_max; + len_buf = 0; + len_full = 0; + require_data = true; + encode = false; + iter = 0; + arg = 0; + do { + /* NOTE: we don't ever want to trust this value for anything + * serious, but the audit record format insists we + * provide an argument length for really long arguments, + * e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but + * to use strncpy_from_user() to obtain this value for + * recording in the log, although we don't use it + * anywhere here to avoid a double-fetch problem */ + if (len_full == 0) + len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1; + + /* read more data from userspace */ + if (require_data) { + /* can we make more room in the buffer? */ + if (buf != buf_head) { + memmove(buf_head, buf, len_buf); + buf = buf_head; + } + + /* fetch as much as we can of the argument */ + len_tmp = strncpy_from_user(&buf_head[len_buf], p, + len_max - len_buf); + if (len_tmp == -EFAULT) { + /* unable to copy from userspace */ + send_sig(SIGKILL, current, 0); + goto out; + } else if (len_tmp == (len_max - len_buf)) { + /* buffer is not large enough */ + require_data = true; + /* NOTE: if we are going to span multiple + * buffers force the encoding so we stand + * a chance at a sane len_full value and + * consistent record encoding */ + encode = true; + len_full = len_full * 2; + p += len_tmp; + } else { + require_data = false; + if (!encode) + encode = audit_string_contains_control( + buf, len_tmp); + /* try to use a trusted value for len_full */ + if (len_full < len_max) + len_full = (encode ? + len_tmp * 2 : len_tmp); + p += len_tmp + 1; + } + len_buf += len_tmp; + buf_head[len_buf] = '\0'; + + /* length of the buffer in the audit record? */ + len_abuf = (encode ? len_buf * 2 : len_buf + 2); + } + + /* write as much as we can to the audit log */ + if (len_buf >= 0) { + /* NOTE: some magic numbers here - basically if we + * can't fit a reasonable amount of data into the + * existing audit buffer, flush it and start with + * a new buffer */ + if ((sizeof(abuf) + 8) > len_rem) { + len_rem = len_max; + audit_log_end(*ab); + *ab = audit_log_start(context, + GFP_KERNEL, AUDIT_EXECVE); + if (!*ab) + goto out; + } + + /* create the non-arg portion of the arg record */ + len_tmp = 0; + if (require_data || (iter > 0) || + ((len_abuf + sizeof(abuf)) > len_rem)) { + if (iter == 0) { + len_tmp += snprintf(&abuf[len_tmp], + sizeof(abuf) - len_tmp, + " a%d_len=%lu", + arg, len_full); + } + len_tmp += snprintf(&abuf[len_tmp], + sizeof(abuf) - len_tmp, + " a%d[%d]=", arg, iter++); + } else + len_tmp += snprintf(&abuf[len_tmp], + sizeof(abuf) - len_tmp, + " a%d=", arg); + WARN_ON(len_tmp >= sizeof(abuf)); + abuf[sizeof(abuf) - 1] = '\0'; + + /* log the arg in the audit record */ + audit_log_format(*ab, "%s", abuf); + len_rem -= len_tmp; + len_tmp = len_buf; + if (encode) { + if (len_abuf > len_rem) + len_tmp = len_rem / 2; /* encoding */ + audit_log_n_hex(*ab, buf, len_tmp); + len_rem -= len_tmp * 2; + len_abuf -= len_tmp * 2; + } else { + if (len_abuf > len_rem) + len_tmp = len_rem - 2; /* quotes */ + audit_log_n_string(*ab, buf, len_tmp); + len_rem -= len_tmp + 2; + /* don't subtract the "2" because we still need + * to add quotes to the remaining string */ + len_abuf -= len_tmp; + } + len_buf -= len_tmp; + buf += len_tmp; + } + + /* ready to move to the next argument? */ + if ((len_buf == 0) && !require_data) { + arg++; + iter = 0; + len_full = 0; + require_data = true; + encode = false; + } + } while (arg < context->execve.argc); + + /* NOTE: the caller handles the final audit_log_end() call */ + +out: + kfree(buf_head); +} + +static void audit_log_cap(struct audit_buffer *ab, char *prefix, + kernel_cap_t *cap) +{ + if (cap_isclear(*cap)) { + audit_log_format(ab, " %s=0", prefix); + return; + } + audit_log_format(ab, " %s=%016llx", prefix, cap->val); +} + +static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) +{ + if (name->fcap_ver == -1) { + audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?"); + return; + } + audit_log_cap(ab, "cap_fp", &name->fcap.permitted); + audit_log_cap(ab, "cap_fi", &name->fcap.inheritable); + audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d", + name->fcap.fE, name->fcap_ver, + from_kuid(&init_user_ns, name->fcap.rootid)); +} + +static void audit_log_time(struct audit_context *context, struct audit_buffer **ab) +{ + const struct audit_ntp_data *ntp = &context->time.ntp_data; + const struct timespec64 *tk = &context->time.tk_injoffset; + static const char * const ntp_name[] = { + "offset", + "freq", + "status", + "tai", + "tick", + "adjust", + }; + int type; + + if (context->type == AUDIT_TIME_ADJNTPVAL) { + for (type = 0; type < AUDIT_NTP_NVALS; type++) { + if (ntp->vals[type].newval != ntp->vals[type].oldval) { + if (!*ab) { + *ab = audit_log_start(context, + GFP_KERNEL, + AUDIT_TIME_ADJNTPVAL); + if (!*ab) + return; + } + audit_log_format(*ab, "op=%s old=%lli new=%lli", + ntp_name[type], + ntp->vals[type].oldval, + ntp->vals[type].newval); + audit_log_end(*ab); + *ab = NULL; + } + } + } + if (tk->tv_sec != 0 || tk->tv_nsec != 0) { + if (!*ab) { + *ab = audit_log_start(context, GFP_KERNEL, + AUDIT_TIME_INJOFFSET); + if (!*ab) + return; + } + audit_log_format(*ab, "sec=%lli nsec=%li", + (long long)tk->tv_sec, tk->tv_nsec); + audit_log_end(*ab); + *ab = NULL; + } +} + +static void show_special(struct audit_context *context, int *call_panic) +{ + struct audit_buffer *ab; + int i; + + ab = audit_log_start(context, GFP_KERNEL, context->type); + if (!ab) + return; + + switch (context->type) { + case AUDIT_SOCKETCALL: { + int nargs = context->socketcall.nargs; + + audit_log_format(ab, "nargs=%d", nargs); + for (i = 0; i < nargs; i++) + audit_log_format(ab, " a%d=%lx", i, + context->socketcall.args[i]); + break; } + case AUDIT_IPC: { + u32 osid = context->ipc.osid; + + audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", + from_kuid(&init_user_ns, context->ipc.uid), + from_kgid(&init_user_ns, context->ipc.gid), + context->ipc.mode); + if (osid) { + char *ctx = NULL; + u32 len; + + if (security_secid_to_secctx(osid, &ctx, &len)) { + audit_log_format(ab, " osid=%u", osid); + *call_panic = 1; + } else { + audit_log_format(ab, " obj=%s", ctx); + security_release_secctx(ctx, len); + } + } + if (context->ipc.has_perm) { + audit_log_end(ab); + ab = audit_log_start(context, GFP_KERNEL, + AUDIT_IPC_SET_PERM); + if (unlikely(!ab)) + return; + audit_log_format(ab, + "qbytes=%lx ouid=%u ogid=%u mode=%#ho", + context->ipc.qbytes, + context->ipc.perm_uid, + context->ipc.perm_gid, + context->ipc.perm_mode); + } + break; } + case AUDIT_MQ_OPEN: + audit_log_format(ab, + "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " + "mq_msgsize=%ld mq_curmsgs=%ld", + context->mq_open.oflag, context->mq_open.mode, + context->mq_open.attr.mq_flags, + context->mq_open.attr.mq_maxmsg, + context->mq_open.attr.mq_msgsize, + context->mq_open.attr.mq_curmsgs); + break; + case AUDIT_MQ_SENDRECV: + audit_log_format(ab, + "mqdes=%d msg_len=%zd msg_prio=%u " + "abs_timeout_sec=%lld abs_timeout_nsec=%ld", + context->mq_sendrecv.mqdes, + context->mq_sendrecv.msg_len, + context->mq_sendrecv.msg_prio, + (long long) context->mq_sendrecv.abs_timeout.tv_sec, + context->mq_sendrecv.abs_timeout.tv_nsec); + break; + case AUDIT_MQ_NOTIFY: + audit_log_format(ab, "mqdes=%d sigev_signo=%d", + context->mq_notify.mqdes, + context->mq_notify.sigev_signo); + break; + case AUDIT_MQ_GETSETATTR: { + struct mq_attr *attr = &context->mq_getsetattr.mqstat; + + audit_log_format(ab, + "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " + "mq_curmsgs=%ld ", + context->mq_getsetattr.mqdes, + attr->mq_flags, attr->mq_maxmsg, + attr->mq_msgsize, attr->mq_curmsgs); + break; } + case AUDIT_CAPSET: + audit_log_format(ab, "pid=%d", context->capset.pid); + audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); + audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); + audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); + audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient); + break; + case AUDIT_MMAP: + audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, + context->mmap.flags); + break; + case AUDIT_OPENAT2: + audit_log_format(ab, "oflag=0%llo mode=0%llo resolve=0x%llx", + context->openat2.flags, + context->openat2.mode, + context->openat2.resolve); + break; + case AUDIT_EXECVE: + audit_log_execve_info(context, &ab); + break; + case AUDIT_KERN_MODULE: + audit_log_format(ab, "name="); + if (context->module.name) { + audit_log_untrustedstring(ab, context->module.name); + } else + audit_log_format(ab, "(null)"); + + break; + case AUDIT_TIME_ADJNTPVAL: + case AUDIT_TIME_INJOFFSET: + /* this call deviates from the rest, eating the buffer */ + audit_log_time(context, &ab); + break; + } + audit_log_end(ab); +} + +static inline int audit_proctitle_rtrim(char *proctitle, int len) +{ + char *end = proctitle + len - 1; + + while (end > proctitle && !isprint(*end)) + end--; + + /* catch the case where proctitle is only 1 non-print character */ + len = end - proctitle + 1; + len -= isprint(proctitle[len-1]) == 0; + return len; +} + +/* + * audit_log_name - produce AUDIT_PATH record from struct audit_names + * @context: audit_context for the task + * @n: audit_names structure with reportable details + * @path: optional path to report instead of audit_names->name + * @record_num: record number to report when handling a list of names + * @call_panic: optional pointer to int that will be updated if secid fails + */ +static void audit_log_name(struct audit_context *context, struct audit_names *n, + const struct path *path, int record_num, int *call_panic) +{ + struct audit_buffer *ab; + + ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); + if (!ab) + return; + + audit_log_format(ab, "item=%d", record_num); + + if (path) + audit_log_d_path(ab, " name=", path); + else if (n->name) { + switch (n->name_len) { + case AUDIT_NAME_FULL: + /* log the full path */ + audit_log_format(ab, " name="); + audit_log_untrustedstring(ab, n->name->name); + break; + case 0: + /* name was specified as a relative path and the + * directory component is the cwd + */ + if (context->pwd.dentry && context->pwd.mnt) + audit_log_d_path(ab, " name=", &context->pwd); + else + audit_log_format(ab, " name=(null)"); + break; + default: + /* log the name's directory component */ + audit_log_format(ab, " name="); + audit_log_n_untrustedstring(ab, n->name->name, + n->name_len); + } + } else + audit_log_format(ab, " name=(null)"); + + if (n->ino != AUDIT_INO_UNSET) + audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#ho ouid=%u ogid=%u rdev=%02x:%02x", + n->ino, + MAJOR(n->dev), + MINOR(n->dev), + n->mode, + from_kuid(&init_user_ns, n->uid), + from_kgid(&init_user_ns, n->gid), + MAJOR(n->rdev), + MINOR(n->rdev)); + if (n->osid != 0) { + char *ctx = NULL; + u32 len; + + if (security_secid_to_secctx( + n->osid, &ctx, &len)) { + audit_log_format(ab, " osid=%u", n->osid); + if (call_panic) + *call_panic = 2; + } else { + audit_log_format(ab, " obj=%s", ctx); + security_release_secctx(ctx, len); + } + } + + /* log the audit_names record type */ + switch (n->type) { + case AUDIT_TYPE_NORMAL: + audit_log_format(ab, " nametype=NORMAL"); + break; + case AUDIT_TYPE_PARENT: + audit_log_format(ab, " nametype=PARENT"); + break; + case AUDIT_TYPE_CHILD_DELETE: + audit_log_format(ab, " nametype=DELETE"); + break; + case AUDIT_TYPE_CHILD_CREATE: + audit_log_format(ab, " nametype=CREATE"); + break; + default: + audit_log_format(ab, " nametype=UNKNOWN"); + break; + } + + audit_log_fcaps(ab, n); + audit_log_end(ab); +} + +static void audit_log_proctitle(void) +{ + int res; + char *buf; + char *msg = "(null)"; + int len = strlen(msg); + struct audit_context *context = audit_context(); + struct audit_buffer *ab; + + ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE); + if (!ab) + return; /* audit_panic or being filtered */ + + audit_log_format(ab, "proctitle="); + + /* Not cached */ + if (!context->proctitle.value) { + buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL); + if (!buf) + goto out; + /* Historically called this from procfs naming */ + res = get_cmdline(current, buf, MAX_PROCTITLE_AUDIT_LEN); + if (res == 0) { + kfree(buf); + goto out; + } + res = audit_proctitle_rtrim(buf, res); + if (res == 0) { + kfree(buf); + goto out; + } + context->proctitle.value = buf; + context->proctitle.len = res; + } + msg = context->proctitle.value; + len = context->proctitle.len; +out: + audit_log_n_untrustedstring(ab, msg, len); + audit_log_end(ab); +} + +/** + * audit_log_uring - generate a AUDIT_URINGOP record + * @ctx: the audit context + */ +static void audit_log_uring(struct audit_context *ctx) +{ + struct audit_buffer *ab; + const struct cred *cred; + + ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_URINGOP); + if (!ab) + return; + cred = current_cred(); + audit_log_format(ab, "uring_op=%d", ctx->uring_op); + if (ctx->return_valid != AUDITSC_INVALID) + audit_log_format(ab, " success=%s exit=%ld", + (ctx->return_valid == AUDITSC_SUCCESS ? + "yes" : "no"), + ctx->return_code); + audit_log_format(ab, + " items=%d" + " ppid=%d pid=%d uid=%u gid=%u euid=%u suid=%u" + " fsuid=%u egid=%u sgid=%u fsgid=%u", + ctx->name_count, + task_ppid_nr(current), task_tgid_nr(current), + from_kuid(&init_user_ns, cred->uid), + from_kgid(&init_user_ns, cred->gid), + from_kuid(&init_user_ns, cred->euid), + from_kuid(&init_user_ns, cred->suid), + from_kuid(&init_user_ns, cred->fsuid), + from_kgid(&init_user_ns, cred->egid), + from_kgid(&init_user_ns, cred->sgid), + from_kgid(&init_user_ns, cred->fsgid)); + audit_log_task_context(ab); + audit_log_key(ab, ctx->filterkey); + audit_log_end(ab); +} + +static void audit_log_exit(void) +{ + int i, call_panic = 0; + struct audit_context *context = audit_context(); + struct audit_buffer *ab; + struct audit_aux_data *aux; + struct audit_names *n; + + context->personality = current->personality; + + switch (context->context) { + case AUDIT_CTX_SYSCALL: + ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); + if (!ab) + return; + audit_log_format(ab, "arch=%x syscall=%d", + context->arch, context->major); + if (context->personality != PER_LINUX) + audit_log_format(ab, " per=%lx", context->personality); + if (context->return_valid != AUDITSC_INVALID) + audit_log_format(ab, " success=%s exit=%ld", + (context->return_valid == AUDITSC_SUCCESS ? + "yes" : "no"), + context->return_code); + audit_log_format(ab, + " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", + context->argv[0], + context->argv[1], + context->argv[2], + context->argv[3], + context->name_count); + audit_log_task_info(ab); + audit_log_key(ab, context->filterkey); + audit_log_end(ab); + break; + case AUDIT_CTX_URING: + audit_log_uring(context); + break; + default: + BUG(); + break; + } + + for (aux = context->aux; aux; aux = aux->next) { + + ab = audit_log_start(context, GFP_KERNEL, aux->type); + if (!ab) + continue; /* audit_panic has been called */ + + switch (aux->type) { + + case AUDIT_BPRM_FCAPS: { + struct audit_aux_data_bprm_fcaps *axs = (void *)aux; + + audit_log_format(ab, "fver=%x", axs->fcap_ver); + audit_log_cap(ab, "fp", &axs->fcap.permitted); + audit_log_cap(ab, "fi", &axs->fcap.inheritable); + audit_log_format(ab, " fe=%d", axs->fcap.fE); + audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); + audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); + audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); + audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient); + audit_log_cap(ab, "pp", &axs->new_pcap.permitted); + audit_log_cap(ab, "pi", &axs->new_pcap.inheritable); + audit_log_cap(ab, "pe", &axs->new_pcap.effective); + audit_log_cap(ab, "pa", &axs->new_pcap.ambient); + audit_log_format(ab, " frootid=%d", + from_kuid(&init_user_ns, + axs->fcap.rootid)); + break; } + + } + audit_log_end(ab); + } + + if (context->type) + show_special(context, &call_panic); + + if (context->fds[0] >= 0) { + ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); + if (ab) { + audit_log_format(ab, "fd0=%d fd1=%d", + context->fds[0], context->fds[1]); + audit_log_end(ab); + } + } + + if (context->sockaddr_len) { + ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); + if (ab) { + audit_log_format(ab, "saddr="); + audit_log_n_hex(ab, (void *)context->sockaddr, + context->sockaddr_len); + audit_log_end(ab); + } + } + + for (aux = context->aux_pids; aux; aux = aux->next) { + struct audit_aux_data_pids *axs = (void *)aux; + + for (i = 0; i < axs->pid_count; i++) + if (audit_log_pid_context(context, axs->target_pid[i], + axs->target_auid[i], + axs->target_uid[i], + axs->target_sessionid[i], + axs->target_sid[i], + axs->target_comm[i])) + call_panic = 1; + } + + if (context->target_pid && + audit_log_pid_context(context, context->target_pid, + context->target_auid, context->target_uid, + context->target_sessionid, + context->target_sid, context->target_comm)) + call_panic = 1; + + if (context->pwd.dentry && context->pwd.mnt) { + ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); + if (ab) { + audit_log_d_path(ab, "cwd=", &context->pwd); + audit_log_end(ab); + } + } + + i = 0; + list_for_each_entry(n, &context->names_list, list) { + if (n->hidden) + continue; + audit_log_name(context, n, NULL, i++, &call_panic); + } + + if (context->context == AUDIT_CTX_SYSCALL) + audit_log_proctitle(); + + /* Send end of event record to help user space know we are finished */ + ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); + if (ab) + audit_log_end(ab); + if (call_panic) + audit_panic("error in audit_log_exit()"); +} + +/** + * __audit_free - free a per-task audit context + * @tsk: task whose audit context block to free + * + * Called from copy_process, do_exit, and the io_uring code + */ +void __audit_free(struct task_struct *tsk) +{ + struct audit_context *context = tsk->audit_context; + + if (!context) + return; + + /* this may generate CONFIG_CHANGE records */ + if (!list_empty(&context->killed_trees)) + audit_kill_trees(context); + + /* We are called either by do_exit() or the fork() error handling code; + * in the former case tsk == current and in the latter tsk is a + * random task_struct that doesn't have any meaningful data we + * need to log via audit_log_exit(). + */ + if (tsk == current && !context->dummy) { + context->return_valid = AUDITSC_INVALID; + context->return_code = 0; + if (context->context == AUDIT_CTX_SYSCALL) { + audit_filter_syscall(tsk, context); + audit_filter_inodes(tsk, context); + if (context->current_state == AUDIT_STATE_RECORD) + audit_log_exit(); + } else if (context->context == AUDIT_CTX_URING) { + /* TODO: verify this case is real and valid */ + audit_filter_uring(tsk, context); + audit_filter_inodes(tsk, context); + if (context->current_state == AUDIT_STATE_RECORD) + audit_log_uring(context); + } + } + + audit_set_context(tsk, NULL); + audit_free_context(context); +} + +/** + * audit_return_fixup - fixup the return codes in the audit_context + * @ctx: the audit_context + * @success: true/false value to indicate if the operation succeeded or not + * @code: operation return code + * + * We need to fixup the return code in the audit logs if the actual return + * codes are later going to be fixed by the arch specific signal handlers. + */ +static void audit_return_fixup(struct audit_context *ctx, + int success, long code) +{ + /* + * This is actually a test for: + * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || + * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) + * + * but is faster than a bunch of || + */ + if (unlikely(code <= -ERESTARTSYS) && + (code >= -ERESTART_RESTARTBLOCK) && + (code != -ENOIOCTLCMD)) + ctx->return_code = -EINTR; + else + ctx->return_code = code; + ctx->return_valid = (success ? AUDITSC_SUCCESS : AUDITSC_FAILURE); +} + +/** + * __audit_uring_entry - prepare the kernel task's audit context for io_uring + * @op: the io_uring opcode + * + * This is similar to audit_syscall_entry() but is intended for use by io_uring + * operations. This function should only ever be called from + * audit_uring_entry() as we rely on the audit context checking present in that + * function. + */ +void __audit_uring_entry(u8 op) +{ + struct audit_context *ctx = audit_context(); + + if (ctx->state == AUDIT_STATE_DISABLED) + return; + + /* + * NOTE: It's possible that we can be called from the process' context + * before it returns to userspace, and before audit_syscall_exit() + * is called. In this case there is not much to do, just record + * the io_uring details and return. + */ + ctx->uring_op = op; + if (ctx->context == AUDIT_CTX_SYSCALL) + return; + + ctx->dummy = !audit_n_rules; + if (!ctx->dummy && ctx->state == AUDIT_STATE_BUILD) + ctx->prio = 0; + + ctx->context = AUDIT_CTX_URING; + ctx->current_state = ctx->state; + ktime_get_coarse_real_ts64(&ctx->ctime); +} + +/** + * __audit_uring_exit - wrap up the kernel task's audit context after io_uring + * @success: true/false value to indicate if the operation succeeded or not + * @code: operation return code + * + * This is similar to audit_syscall_exit() but is intended for use by io_uring + * operations. This function should only ever be called from + * audit_uring_exit() as we rely on the audit context checking present in that + * function. + */ +void __audit_uring_exit(int success, long code) +{ + struct audit_context *ctx = audit_context(); + + if (ctx->dummy) { + if (ctx->context != AUDIT_CTX_URING) + return; + goto out; + } + + audit_return_fixup(ctx, success, code); + if (ctx->context == AUDIT_CTX_SYSCALL) { + /* + * NOTE: See the note in __audit_uring_entry() about the case + * where we may be called from process context before we + * return to userspace via audit_syscall_exit(). In this + * case we simply emit a URINGOP record and bail, the + * normal syscall exit handling will take care of + * everything else. + * It is also worth mentioning that when we are called, + * the current process creds may differ from the creds + * used during the normal syscall processing; keep that + * in mind if/when we move the record generation code. + */ + + /* + * We need to filter on the syscall info here to decide if we + * should emit a URINGOP record. I know it seems odd but this + * solves the problem where users have a filter to block *all* + * syscall records in the "exit" filter; we want to preserve + * the behavior here. + */ + audit_filter_syscall(current, ctx); + if (ctx->current_state != AUDIT_STATE_RECORD) + audit_filter_uring(current, ctx); + audit_filter_inodes(current, ctx); + if (ctx->current_state != AUDIT_STATE_RECORD) + return; + + audit_log_uring(ctx); + return; + } + + /* this may generate CONFIG_CHANGE records */ + if (!list_empty(&ctx->killed_trees)) + audit_kill_trees(ctx); + + /* run through both filters to ensure we set the filterkey properly */ + audit_filter_uring(current, ctx); + audit_filter_inodes(current, ctx); + if (ctx->current_state != AUDIT_STATE_RECORD) + goto out; + audit_log_exit(); + +out: + audit_reset_context(ctx); +} + +/** + * __audit_syscall_entry - fill in an audit record at syscall entry + * @major: major syscall type (function) + * @a1: additional syscall register 1 + * @a2: additional syscall register 2 + * @a3: additional syscall register 3 + * @a4: additional syscall register 4 + * + * Fill in audit context at syscall entry. This only happens if the + * audit context was created when the task was created and the state or + * filters demand the audit context be built. If the state from the + * per-task filter or from the per-syscall filter is AUDIT_STATE_RECORD, + * then the record will be written at syscall exit time (otherwise, it + * will only be written if another part of the kernel requests that it + * be written). + */ +void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2, + unsigned long a3, unsigned long a4) +{ + struct audit_context *context = audit_context(); + enum audit_state state; + + if (!audit_enabled || !context) + return; + + WARN_ON(context->context != AUDIT_CTX_UNUSED); + WARN_ON(context->name_count); + if (context->context != AUDIT_CTX_UNUSED || context->name_count) { + audit_panic("unrecoverable error in audit_syscall_entry()"); + return; + } + + state = context->state; + if (state == AUDIT_STATE_DISABLED) + return; + + context->dummy = !audit_n_rules; + if (!context->dummy && state == AUDIT_STATE_BUILD) { + context->prio = 0; + if (auditd_test_task(current)) + return; + } + + context->arch = syscall_get_arch(current); + context->major = major; + context->argv[0] = a1; + context->argv[1] = a2; + context->argv[2] = a3; + context->argv[3] = a4; + context->context = AUDIT_CTX_SYSCALL; + context->current_state = state; + ktime_get_coarse_real_ts64(&context->ctime); +} + +/** + * __audit_syscall_exit - deallocate audit context after a system call + * @success: success value of the syscall + * @return_code: return value of the syscall + * + * Tear down after system call. If the audit context has been marked as + * auditable (either because of the AUDIT_STATE_RECORD state from + * filtering, or because some other part of the kernel wrote an audit + * message), then write out the syscall information. In call cases, + * free the names stored from getname(). + */ +void __audit_syscall_exit(int success, long return_code) +{ + struct audit_context *context = audit_context(); + + if (!context || context->dummy || + context->context != AUDIT_CTX_SYSCALL) + goto out; + + /* this may generate CONFIG_CHANGE records */ + if (!list_empty(&context->killed_trees)) + audit_kill_trees(context); + + audit_return_fixup(context, success, return_code); + /* run through both filters to ensure we set the filterkey properly */ + audit_filter_syscall(current, context); + audit_filter_inodes(current, context); + if (context->current_state != AUDIT_STATE_RECORD) + goto out; + + audit_log_exit(); + +out: + audit_reset_context(context); +} + +static inline void handle_one(const struct inode *inode) +{ + struct audit_context *context; + struct audit_tree_refs *p; + struct audit_chunk *chunk; + int count; + + if (likely(!inode->i_fsnotify_marks)) + return; + context = audit_context(); + p = context->trees; + count = context->tree_count; + rcu_read_lock(); + chunk = audit_tree_lookup(inode); + rcu_read_unlock(); + if (!chunk) + return; + if (likely(put_tree_ref(context, chunk))) + return; + if (unlikely(!grow_tree_refs(context))) { + pr_warn("out of memory, audit has lost a tree reference\n"); + audit_set_auditable(context); + audit_put_chunk(chunk); + unroll_tree_refs(context, p, count); + return; + } + put_tree_ref(context, chunk); +} + +static void handle_path(const struct dentry *dentry) +{ + struct audit_context *context; + struct audit_tree_refs *p; + const struct dentry *d, *parent; + struct audit_chunk *drop; + unsigned long seq; + int count; + + context = audit_context(); + p = context->trees; + count = context->tree_count; +retry: + drop = NULL; + d = dentry; + rcu_read_lock(); + seq = read_seqbegin(&rename_lock); + for (;;) { + struct inode *inode = d_backing_inode(d); + + if (inode && unlikely(inode->i_fsnotify_marks)) { + struct audit_chunk *chunk; + + chunk = audit_tree_lookup(inode); + if (chunk) { + if (unlikely(!put_tree_ref(context, chunk))) { + drop = chunk; + break; + } + } + } + parent = d->d_parent; + if (parent == d) + break; + d = parent; + } + if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ + rcu_read_unlock(); + if (!drop) { + /* just a race with rename */ + unroll_tree_refs(context, p, count); + goto retry; + } + audit_put_chunk(drop); + if (grow_tree_refs(context)) { + /* OK, got more space */ + unroll_tree_refs(context, p, count); + goto retry; + } + /* too bad */ + pr_warn("out of memory, audit has lost a tree reference\n"); + unroll_tree_refs(context, p, count); + audit_set_auditable(context); + return; + } + rcu_read_unlock(); +} + +static struct audit_names *audit_alloc_name(struct audit_context *context, + unsigned char type) +{ + struct audit_names *aname; + + if (context->name_count < AUDIT_NAMES) { + aname = &context->preallocated_names[context->name_count]; + memset(aname, 0, sizeof(*aname)); + } else { + aname = kzalloc(sizeof(*aname), GFP_NOFS); + if (!aname) + return NULL; + aname->should_free = true; + } + + aname->ino = AUDIT_INO_UNSET; + aname->type = type; + list_add_tail(&aname->list, &context->names_list); + + context->name_count++; + if (!context->pwd.dentry) + get_fs_pwd(current->fs, &context->pwd); + return aname; +} + +/** + * __audit_reusename - fill out filename with info from existing entry + * @uptr: userland ptr to pathname + * + * Search the audit_names list for the current audit context. If there is an + * existing entry with a matching "uptr" then return the filename + * associated with that audit_name. If not, return NULL. + */ +struct filename * +__audit_reusename(const __user char *uptr) +{ + struct audit_context *context = audit_context(); + struct audit_names *n; + + list_for_each_entry(n, &context->names_list, list) { + if (!n->name) + continue; + if (n->name->uptr == uptr) { + atomic_inc(&n->name->refcnt); + return n->name; + } + } + return NULL; +} + +/** + * __audit_getname - add a name to the list + * @name: name to add + * + * Add a name to the list of audit names for this context. + * Called from fs/namei.c:getname(). + */ +void __audit_getname(struct filename *name) +{ + struct audit_context *context = audit_context(); + struct audit_names *n; + + if (context->context == AUDIT_CTX_UNUSED) + return; + + n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); + if (!n) + return; + + n->name = name; + n->name_len = AUDIT_NAME_FULL; + name->aname = n; + atomic_inc(&name->refcnt); +} + +static inline int audit_copy_fcaps(struct audit_names *name, + const struct dentry *dentry) +{ + struct cpu_vfs_cap_data caps; + int rc; + + if (!dentry) + return 0; + + rc = get_vfs_caps_from_disk(&nop_mnt_idmap, dentry, &caps); + if (rc) + return rc; + + name->fcap.permitted = caps.permitted; + name->fcap.inheritable = caps.inheritable; + name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); + name->fcap.rootid = caps.rootid; + name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> + VFS_CAP_REVISION_SHIFT; + + return 0; +} + +/* Copy inode data into an audit_names. */ +static void audit_copy_inode(struct audit_names *name, + const struct dentry *dentry, + struct inode *inode, unsigned int flags) +{ + name->ino = inode->i_ino; + name->dev = inode->i_sb->s_dev; + name->mode = inode->i_mode; + name->uid = inode->i_uid; + name->gid = inode->i_gid; + name->rdev = inode->i_rdev; + security_inode_getsecid(inode, &name->osid); + if (flags & AUDIT_INODE_NOEVAL) { + name->fcap_ver = -1; + return; + } + audit_copy_fcaps(name, dentry); +} + +/** + * __audit_inode - store the inode and device from a lookup + * @name: name being audited + * @dentry: dentry being audited + * @flags: attributes for this particular entry + */ +void __audit_inode(struct filename *name, const struct dentry *dentry, + unsigned int flags) +{ + struct audit_context *context = audit_context(); + struct inode *inode = d_backing_inode(dentry); + struct audit_names *n; + bool parent = flags & AUDIT_INODE_PARENT; + struct audit_entry *e; + struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; + int i; + + if (context->context == AUDIT_CTX_UNUSED) + return; + + rcu_read_lock(); + list_for_each_entry_rcu(e, list, list) { + for (i = 0; i < e->rule.field_count; i++) { + struct audit_field *f = &e->rule.fields[i]; + + if (f->type == AUDIT_FSTYPE + && audit_comparator(inode->i_sb->s_magic, + f->op, f->val) + && e->rule.action == AUDIT_NEVER) { + rcu_read_unlock(); + return; + } + } + } + rcu_read_unlock(); + + if (!name) + goto out_alloc; + + /* + * If we have a pointer to an audit_names entry already, then we can + * just use it directly if the type is correct. + */ + n = name->aname; + if (n) { + if (parent) { + if (n->type == AUDIT_TYPE_PARENT || + n->type == AUDIT_TYPE_UNKNOWN) + goto out; + } else { + if (n->type != AUDIT_TYPE_PARENT) + goto out; + } + } + + list_for_each_entry_reverse(n, &context->names_list, list) { + if (n->ino) { + /* valid inode number, use that for the comparison */ + if (n->ino != inode->i_ino || + n->dev != inode->i_sb->s_dev) + continue; + } else if (n->name) { + /* inode number has not been set, check the name */ + if (strcmp(n->name->name, name->name)) + continue; + } else + /* no inode and no name (?!) ... this is odd ... */ + continue; + + /* match the correct record type */ + if (parent) { + if (n->type == AUDIT_TYPE_PARENT || + n->type == AUDIT_TYPE_UNKNOWN) + goto out; + } else { + if (n->type != AUDIT_TYPE_PARENT) + goto out; + } + } + +out_alloc: + /* unable to find an entry with both a matching name and type */ + n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); + if (!n) + return; + if (name) { + n->name = name; + atomic_inc(&name->refcnt); + } + +out: + if (parent) { + n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL; + n->type = AUDIT_TYPE_PARENT; + if (flags & AUDIT_INODE_HIDDEN) + n->hidden = true; + } else { + n->name_len = AUDIT_NAME_FULL; + n->type = AUDIT_TYPE_NORMAL; + } + handle_path(dentry); + audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL); +} + +void __audit_file(const struct file *file) +{ + __audit_inode(NULL, file->f_path.dentry, 0); +} + +/** + * __audit_inode_child - collect inode info for created/removed objects + * @parent: inode of dentry parent + * @dentry: dentry being audited + * @type: AUDIT_TYPE_* value that we're looking for + * + * For syscalls that create or remove filesystem objects, audit_inode + * can only collect information for the filesystem object's parent. + * This call updates the audit context with the child's information. + * Syscalls that create a new filesystem object must be hooked after + * the object is created. Syscalls that remove a filesystem object + * must be hooked prior, in order to capture the target inode during + * unsuccessful attempts. + */ +void __audit_inode_child(struct inode *parent, + const struct dentry *dentry, + const unsigned char type) +{ + struct audit_context *context = audit_context(); + struct inode *inode = d_backing_inode(dentry); + const struct qstr *dname = &dentry->d_name; + struct audit_names *n, *found_parent = NULL, *found_child = NULL; + struct audit_entry *e; + struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; + int i; + + if (context->context == AUDIT_CTX_UNUSED) + return; + + rcu_read_lock(); + list_for_each_entry_rcu(e, list, list) { + for (i = 0; i < e->rule.field_count; i++) { + struct audit_field *f = &e->rule.fields[i]; + + if (f->type == AUDIT_FSTYPE + && audit_comparator(parent->i_sb->s_magic, + f->op, f->val) + && e->rule.action == AUDIT_NEVER) { + rcu_read_unlock(); + return; + } + } + } + rcu_read_unlock(); + + if (inode) + handle_one(inode); + + /* look for a parent entry first */ + list_for_each_entry(n, &context->names_list, list) { + if (!n->name || + (n->type != AUDIT_TYPE_PARENT && + n->type != AUDIT_TYPE_UNKNOWN)) + continue; + + if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev && + !audit_compare_dname_path(dname, + n->name->name, n->name_len)) { + if (n->type == AUDIT_TYPE_UNKNOWN) + n->type = AUDIT_TYPE_PARENT; + found_parent = n; + break; + } + } + + cond_resched(); + + /* is there a matching child entry? */ + list_for_each_entry(n, &context->names_list, list) { + /* can only match entries that have a name */ + if (!n->name || + (n->type != type && n->type != AUDIT_TYPE_UNKNOWN)) + continue; + + if (!strcmp(dname->name, n->name->name) || + !audit_compare_dname_path(dname, n->name->name, + found_parent ? + found_parent->name_len : + AUDIT_NAME_FULL)) { + if (n->type == AUDIT_TYPE_UNKNOWN) + n->type = type; + found_child = n; + break; + } + } + + if (!found_parent) { + /* create a new, "anonymous" parent record */ + n = audit_alloc_name(context, AUDIT_TYPE_PARENT); + if (!n) + return; + audit_copy_inode(n, NULL, parent, 0); + } + + if (!found_child) { + found_child = audit_alloc_name(context, type); + if (!found_child) + return; + + /* Re-use the name belonging to the slot for a matching parent + * directory. All names for this context are relinquished in + * audit_free_names() */ + if (found_parent) { + found_child->name = found_parent->name; + found_child->name_len = AUDIT_NAME_FULL; + atomic_inc(&found_child->name->refcnt); + } + } + + if (inode) + audit_copy_inode(found_child, dentry, inode, 0); + else + found_child->ino = AUDIT_INO_UNSET; +} +EXPORT_SYMBOL_GPL(__audit_inode_child); + +/** + * auditsc_get_stamp - get local copies of audit_context values + * @ctx: audit_context for the task + * @t: timespec64 to store time recorded in the audit_context + * @serial: serial value that is recorded in the audit_context + * + * Also sets the context as auditable. + */ +int auditsc_get_stamp(struct audit_context *ctx, + struct timespec64 *t, unsigned int *serial) +{ + if (ctx->context == AUDIT_CTX_UNUSED) + return 0; + if (!ctx->serial) + ctx->serial = audit_serial(); + t->tv_sec = ctx->ctime.tv_sec; + t->tv_nsec = ctx->ctime.tv_nsec; + *serial = ctx->serial; + if (!ctx->prio) { + ctx->prio = 1; + ctx->current_state = AUDIT_STATE_RECORD; + } + return 1; +} + +/** + * __audit_mq_open - record audit data for a POSIX MQ open + * @oflag: open flag + * @mode: mode bits + * @attr: queue attributes + * + */ +void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) +{ + struct audit_context *context = audit_context(); + + if (attr) + memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); + else + memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); + + context->mq_open.oflag = oflag; + context->mq_open.mode = mode; + + context->type = AUDIT_MQ_OPEN; +} + +/** + * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive + * @mqdes: MQ descriptor + * @msg_len: Message length + * @msg_prio: Message priority + * @abs_timeout: Message timeout in absolute time + * + */ +void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, + const struct timespec64 *abs_timeout) +{ + struct audit_context *context = audit_context(); + struct timespec64 *p = &context->mq_sendrecv.abs_timeout; + + if (abs_timeout) + memcpy(p, abs_timeout, sizeof(*p)); + else + memset(p, 0, sizeof(*p)); + + context->mq_sendrecv.mqdes = mqdes; + context->mq_sendrecv.msg_len = msg_len; + context->mq_sendrecv.msg_prio = msg_prio; + + context->type = AUDIT_MQ_SENDRECV; +} + +/** + * __audit_mq_notify - record audit data for a POSIX MQ notify + * @mqdes: MQ descriptor + * @notification: Notification event + * + */ + +void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) +{ + struct audit_context *context = audit_context(); + + if (notification) + context->mq_notify.sigev_signo = notification->sigev_signo; + else + context->mq_notify.sigev_signo = 0; + + context->mq_notify.mqdes = mqdes; + context->type = AUDIT_MQ_NOTIFY; +} + +/** + * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute + * @mqdes: MQ descriptor + * @mqstat: MQ flags + * + */ +void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) +{ + struct audit_context *context = audit_context(); + + context->mq_getsetattr.mqdes = mqdes; + context->mq_getsetattr.mqstat = *mqstat; + context->type = AUDIT_MQ_GETSETATTR; +} + +/** + * __audit_ipc_obj - record audit data for ipc object + * @ipcp: ipc permissions + * + */ +void __audit_ipc_obj(struct kern_ipc_perm *ipcp) +{ + struct audit_context *context = audit_context(); + + context->ipc.uid = ipcp->uid; + context->ipc.gid = ipcp->gid; + context->ipc.mode = ipcp->mode; + context->ipc.has_perm = 0; + security_ipc_getsecid(ipcp, &context->ipc.osid); + context->type = AUDIT_IPC; +} + +/** + * __audit_ipc_set_perm - record audit data for new ipc permissions + * @qbytes: msgq bytes + * @uid: msgq user id + * @gid: msgq group id + * @mode: msgq mode (permissions) + * + * Called only after audit_ipc_obj(). + */ +void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) +{ + struct audit_context *context = audit_context(); + + context->ipc.qbytes = qbytes; + context->ipc.perm_uid = uid; + context->ipc.perm_gid = gid; + context->ipc.perm_mode = mode; + context->ipc.has_perm = 1; +} + +void __audit_bprm(struct linux_binprm *bprm) +{ + struct audit_context *context = audit_context(); + + context->type = AUDIT_EXECVE; + context->execve.argc = bprm->argc; +} + + +/** + * __audit_socketcall - record audit data for sys_socketcall + * @nargs: number of args, which should not be more than AUDITSC_ARGS. + * @args: args array + * + */ +int __audit_socketcall(int nargs, unsigned long *args) +{ + struct audit_context *context = audit_context(); + + if (nargs <= 0 || nargs > AUDITSC_ARGS || !args) + return -EINVAL; + context->type = AUDIT_SOCKETCALL; + context->socketcall.nargs = nargs; + memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); + return 0; +} + +/** + * __audit_fd_pair - record audit data for pipe and socketpair + * @fd1: the first file descriptor + * @fd2: the second file descriptor + * + */ +void __audit_fd_pair(int fd1, int fd2) +{ + struct audit_context *context = audit_context(); + + context->fds[0] = fd1; + context->fds[1] = fd2; +} + +/** + * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto + * @len: data length in user space + * @a: data address in kernel space + * + * Returns 0 for success or NULL context or < 0 on error. + */ +int __audit_sockaddr(int len, void *a) +{ + struct audit_context *context = audit_context(); + + if (!context->sockaddr) { + void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); + + if (!p) + return -ENOMEM; + context->sockaddr = p; + } + + context->sockaddr_len = len; + memcpy(context->sockaddr, a, len); + return 0; +} + +void __audit_ptrace(struct task_struct *t) +{ + struct audit_context *context = audit_context(); + + context->target_pid = task_tgid_nr(t); + context->target_auid = audit_get_loginuid(t); + context->target_uid = task_uid(t); + context->target_sessionid = audit_get_sessionid(t); + security_task_getsecid_obj(t, &context->target_sid); + memcpy(context->target_comm, t->comm, TASK_COMM_LEN); +} + +/** + * audit_signal_info_syscall - record signal info for syscalls + * @t: task being signaled + * + * If the audit subsystem is being terminated, record the task (pid) + * and uid that is doing that. + */ +int audit_signal_info_syscall(struct task_struct *t) +{ + struct audit_aux_data_pids *axp; + struct audit_context *ctx = audit_context(); + kuid_t t_uid = task_uid(t); + + if (!audit_signals || audit_dummy_context()) + return 0; + + /* optimize the common case by putting first signal recipient directly + * in audit_context */ + if (!ctx->target_pid) { + ctx->target_pid = task_tgid_nr(t); + ctx->target_auid = audit_get_loginuid(t); + ctx->target_uid = t_uid; + ctx->target_sessionid = audit_get_sessionid(t); + security_task_getsecid_obj(t, &ctx->target_sid); + memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); + return 0; + } + + axp = (void *)ctx->aux_pids; + if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { + axp = kzalloc(sizeof(*axp), GFP_ATOMIC); + if (!axp) + return -ENOMEM; + + axp->d.type = AUDIT_OBJ_PID; + axp->d.next = ctx->aux_pids; + ctx->aux_pids = (void *)axp; + } + BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); + + axp->target_pid[axp->pid_count] = task_tgid_nr(t); + axp->target_auid[axp->pid_count] = audit_get_loginuid(t); + axp->target_uid[axp->pid_count] = t_uid; + axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); + security_task_getsecid_obj(t, &axp->target_sid[axp->pid_count]); + memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); + axp->pid_count++; + + return 0; +} + +/** + * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps + * @bprm: pointer to the bprm being processed + * @new: the proposed new credentials + * @old: the old credentials + * + * Simply check if the proc already has the caps given by the file and if not + * store the priv escalation info for later auditing at the end of the syscall + * + * -Eric + */ +int __audit_log_bprm_fcaps(struct linux_binprm *bprm, + const struct cred *new, const struct cred *old) +{ + struct audit_aux_data_bprm_fcaps *ax; + struct audit_context *context = audit_context(); + struct cpu_vfs_cap_data vcaps; + + ax = kmalloc(sizeof(*ax), GFP_KERNEL); + if (!ax) + return -ENOMEM; + + ax->d.type = AUDIT_BPRM_FCAPS; + ax->d.next = context->aux; + context->aux = (void *)ax; + + get_vfs_caps_from_disk(&nop_mnt_idmap, + bprm->file->f_path.dentry, &vcaps); + + ax->fcap.permitted = vcaps.permitted; + ax->fcap.inheritable = vcaps.inheritable; + ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); + ax->fcap.rootid = vcaps.rootid; + ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; + + ax->old_pcap.permitted = old->cap_permitted; + ax->old_pcap.inheritable = old->cap_inheritable; + ax->old_pcap.effective = old->cap_effective; + ax->old_pcap.ambient = old->cap_ambient; + + ax->new_pcap.permitted = new->cap_permitted; + ax->new_pcap.inheritable = new->cap_inheritable; + ax->new_pcap.effective = new->cap_effective; + ax->new_pcap.ambient = new->cap_ambient; + return 0; +} + +/** + * __audit_log_capset - store information about the arguments to the capset syscall + * @new: the new credentials + * @old: the old (current) credentials + * + * Record the arguments userspace sent to sys_capset for later printing by the + * audit system if applicable + */ +void __audit_log_capset(const struct cred *new, const struct cred *old) +{ + struct audit_context *context = audit_context(); + + context->capset.pid = task_tgid_nr(current); + context->capset.cap.effective = new->cap_effective; + context->capset.cap.inheritable = new->cap_effective; + context->capset.cap.permitted = new->cap_permitted; + context->capset.cap.ambient = new->cap_ambient; + context->type = AUDIT_CAPSET; +} + +void __audit_mmap_fd(int fd, int flags) +{ + struct audit_context *context = audit_context(); + + context->mmap.fd = fd; + context->mmap.flags = flags; + context->type = AUDIT_MMAP; +} + +void __audit_openat2_how(struct open_how *how) +{ + struct audit_context *context = audit_context(); + + context->openat2.flags = how->flags; + context->openat2.mode = how->mode; + context->openat2.resolve = how->resolve; + context->type = AUDIT_OPENAT2; +} + +void __audit_log_kern_module(char *name) +{ + struct audit_context *context = audit_context(); + + context->module.name = kstrdup(name, GFP_KERNEL); + if (!context->module.name) + audit_log_lost("out of memory in __audit_log_kern_module"); + context->type = AUDIT_KERN_MODULE; +} + +void __audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar) +{ + /* {subj,obj}_trust values are {0,1,2}: no,yes,unknown */ + switch (friar->hdr.type) { + case FAN_RESPONSE_INFO_NONE: + audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY, + "resp=%u fan_type=%u fan_info=0 subj_trust=2 obj_trust=2", + response, FAN_RESPONSE_INFO_NONE); + break; + case FAN_RESPONSE_INFO_AUDIT_RULE: + audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY, + "resp=%u fan_type=%u fan_info=%X subj_trust=%u obj_trust=%u", + response, friar->hdr.type, friar->rule_number, + friar->subj_trust, friar->obj_trust); + } +} + +void __audit_tk_injoffset(struct timespec64 offset) +{ + struct audit_context *context = audit_context(); + + /* only set type if not already set by NTP */ + if (!context->type) + context->type = AUDIT_TIME_INJOFFSET; + memcpy(&context->time.tk_injoffset, &offset, sizeof(offset)); +} + +void __audit_ntp_log(const struct audit_ntp_data *ad) +{ + struct audit_context *context = audit_context(); + int type; + + for (type = 0; type < AUDIT_NTP_NVALS; type++) + if (ad->vals[type].newval != ad->vals[type].oldval) { + /* unconditionally set type, overwriting TK */ + context->type = AUDIT_TIME_ADJNTPVAL; + memcpy(&context->time.ntp_data, ad, sizeof(*ad)); + break; + } +} + +void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries, + enum audit_nfcfgop op, gfp_t gfp) +{ + struct audit_buffer *ab; + char comm[sizeof(current->comm)]; + + ab = audit_log_start(audit_context(), gfp, AUDIT_NETFILTER_CFG); + if (!ab) + return; + audit_log_format(ab, "table=%s family=%u entries=%u op=%s", + name, af, nentries, audit_nfcfgs[op].s); + + audit_log_format(ab, " pid=%u", task_pid_nr(current)); + audit_log_task_context(ab); /* subj= */ + audit_log_format(ab, " comm="); + audit_log_untrustedstring(ab, get_task_comm(comm, current)); + audit_log_end(ab); +} +EXPORT_SYMBOL_GPL(__audit_log_nfcfg); + +static void audit_log_task(struct audit_buffer *ab) +{ + kuid_t auid, uid; + kgid_t gid; + unsigned int sessionid; + char comm[sizeof(current->comm)]; + + auid = audit_get_loginuid(current); + sessionid = audit_get_sessionid(current); + current_uid_gid(&uid, &gid); + + audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", + from_kuid(&init_user_ns, auid), + from_kuid(&init_user_ns, uid), + from_kgid(&init_user_ns, gid), + sessionid); + audit_log_task_context(ab); + audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current)); + audit_log_untrustedstring(ab, get_task_comm(comm, current)); + audit_log_d_path_exe(ab, current->mm); +} + +/** + * audit_core_dumps - record information about processes that end abnormally + * @signr: signal value + * + * If a process ends with a core dump, something fishy is going on and we + * should record the event for investigation. + */ +void audit_core_dumps(long signr) +{ + struct audit_buffer *ab; + + if (!audit_enabled) + return; + + if (signr == SIGQUIT) /* don't care for those */ + return; + + ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_ABEND); + if (unlikely(!ab)) + return; + audit_log_task(ab); + audit_log_format(ab, " sig=%ld res=1", signr); + audit_log_end(ab); +} + +/** + * audit_seccomp - record information about a seccomp action + * @syscall: syscall number + * @signr: signal value + * @code: the seccomp action + * + * Record the information associated with a seccomp action. Event filtering for + * seccomp actions that are not to be logged is done in seccomp_log(). + * Therefore, this function forces auditing independent of the audit_enabled + * and dummy context state because seccomp actions should be logged even when + * audit is not in use. + */ +void audit_seccomp(unsigned long syscall, long signr, int code) +{ + struct audit_buffer *ab; + + ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_SECCOMP); + if (unlikely(!ab)) + return; + audit_log_task(ab); + audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x", + signr, syscall_get_arch(current), syscall, + in_compat_syscall(), KSTK_EIP(current), code); + audit_log_end(ab); +} + +void audit_seccomp_actions_logged(const char *names, const char *old_names, + int res) +{ + struct audit_buffer *ab; + + if (!audit_enabled) + return; + + ab = audit_log_start(audit_context(), GFP_KERNEL, + AUDIT_CONFIG_CHANGE); + if (unlikely(!ab)) + return; + + audit_log_format(ab, + "op=seccomp-logging actions=%s old-actions=%s res=%d", + names, old_names, res); + audit_log_end(ab); +} + +struct list_head *audit_killed_trees(void) +{ + struct audit_context *ctx = audit_context(); + if (likely(!ctx || ctx->context == AUDIT_CTX_UNUSED)) + return NULL; + return &ctx->killed_trees; +} |