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-rw-r--r--src/pstore/pstore.c408
1 files changed, 408 insertions, 0 deletions
diff --git a/src/pstore/pstore.c b/src/pstore/pstore.c
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+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+/* Copyright © 2019 Oracle and/or its affiliates. */
+
+/* Generally speaking, the pstore contains a small number of files
+ * that in turn contain a small amount of data. */
+#include <errno.h>
+#include <stdio.h>
+#include <stdio_ext.h>
+#include <sys/prctl.h>
+#include <sys/xattr.h>
+#include <unistd.h>
+
+#include "sd-daemon.h"
+#include "sd-journal.h"
+#include "sd-login.h"
+#include "sd-messages.h"
+
+#include "acl-util.h"
+#include "alloc-util.h"
+#include "capability-util.h"
+#include "cgroup-util.h"
+#include "compress.h"
+#include "conf-parser.h"
+#include "copy.h"
+#include "dirent-util.h"
+#include "escape.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "fs-util.h"
+#include "io-util.h"
+#include "journal-importer.h"
+#include "log.h"
+#include "macro.h"
+#include "main-func.h"
+#include "mkdir.h"
+#include "parse-util.h"
+#include "process-util.h"
+#include "signal-util.h"
+#include "socket-util.h"
+#include "special.h"
+#include "sort-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "strv.h"
+#include "tmpfile-util.h"
+#include "user-util.h"
+#include "util.h"
+
+/* Command line argument handling */
+typedef enum PStoreStorage {
+ PSTORE_STORAGE_NONE,
+ PSTORE_STORAGE_EXTERNAL,
+ PSTORE_STORAGE_JOURNAL,
+ _PSTORE_STORAGE_MAX,
+ _PSTORE_STORAGE_INVALID = -1
+} PStoreStorage;
+
+static const char* const pstore_storage_table[_PSTORE_STORAGE_MAX] = {
+ [PSTORE_STORAGE_NONE] = "none",
+ [PSTORE_STORAGE_EXTERNAL] = "external",
+ [PSTORE_STORAGE_JOURNAL] = "journal",
+};
+
+DEFINE_PRIVATE_STRING_TABLE_LOOKUP(pstore_storage, PStoreStorage);
+static DEFINE_CONFIG_PARSE_ENUM(config_parse_pstore_storage, pstore_storage, PStoreStorage, "Failed to parse storage setting");
+
+static PStoreStorage arg_storage = PSTORE_STORAGE_EXTERNAL;
+
+static bool arg_unlink = true;
+static const char *arg_sourcedir = "/sys/fs/pstore";
+static const char *arg_archivedir = "/var/lib/systemd/pstore";
+
+static int parse_config(void) {
+ static const ConfigTableItem items[] = {
+ { "PStore", "Unlink", config_parse_bool, 0, &arg_unlink },
+ { "PStore", "Storage", config_parse_pstore_storage, 0, &arg_storage },
+ {}
+ };
+
+ return config_parse_many_nulstr(
+ PKGSYSCONFDIR "/pstore.conf",
+ CONF_PATHS_NULSTR("systemd/pstore.conf.d"),
+ "PStore\0",
+ config_item_table_lookup, items,
+ CONFIG_PARSE_WARN,
+ NULL,
+ NULL);
+}
+
+/* File list handling - PStoreEntry is the struct and
+ * and PStoreEntry is the type that contains all info
+ * about a pstore entry. */
+typedef struct PStoreEntry {
+ struct dirent dirent;
+ bool is_binary;
+ bool handled;
+ char *content;
+ size_t content_size;
+} PStoreEntry;
+
+typedef struct PStoreList {
+ PStoreEntry *entries;
+ size_t n_allocated;
+ size_t n_entries;
+} PStoreList;
+
+static void pstore_entries_reset(PStoreList *list) {
+ for (size_t i = 0; i < list->n_entries; i++)
+ free(list->entries[i].content);
+ free(list->entries);
+ list->n_entries = 0;
+}
+
+static int compare_pstore_entries(const PStoreEntry *a, const PStoreEntry *b) {
+ return strcmp(a->dirent.d_name, b->dirent.d_name);
+}
+
+static int move_file(PStoreEntry *pe, const char *subdir) {
+ _cleanup_free_ char *ifd_path = NULL, *ofd_path = NULL;
+ _cleanup_free_ void *field = NULL;
+ const char *suffix, *message;
+ struct iovec iovec[2];
+ int n_iovec = 0, r;
+
+ if (pe->handled)
+ return 0;
+
+ ifd_path = path_join(arg_sourcedir, pe->dirent.d_name);
+ if (!ifd_path)
+ return log_oom();
+
+ ofd_path = path_join(arg_archivedir, subdir, pe->dirent.d_name);
+ if (!ofd_path)
+ return log_oom();
+
+ /* Always log to the journal */
+ suffix = arg_storage == PSTORE_STORAGE_EXTERNAL ? strjoina(" moved to ", ofd_path) : (char *)".";
+ message = strjoina("MESSAGE=PStore ", pe->dirent.d_name, suffix);
+ iovec[n_iovec++] = IOVEC_MAKE_STRING(message);
+
+ if (pe->content_size > 0) {
+ size_t field_size;
+
+ field_size = strlen("FILE=") + pe->content_size;
+ field = malloc(field_size);
+ if (!field)
+ return log_oom();
+ memcpy(stpcpy(field, "FILE="), pe->content, pe->content_size);
+ iovec[n_iovec++] = IOVEC_MAKE(field, field_size);
+ }
+
+ r = sd_journal_sendv(iovec, n_iovec);
+ if (r < 0)
+ return log_error_errno(r, "Failed to log pstore entry: %m");
+
+ if (arg_storage == PSTORE_STORAGE_EXTERNAL) {
+ /* Move file from pstore to external storage */
+ r = mkdir_parents(ofd_path, 0755);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create directory %s: %m", ofd_path);
+ r = copy_file_atomic(ifd_path, ofd_path, 0600, 0, 0, COPY_REPLACE);
+ if (r < 0)
+ return log_error_errno(r, "Failed to copy_file_atomic: %s to %s", ifd_path, ofd_path);
+ }
+
+ /* If file copied properly, remove it from pstore */
+ if (arg_unlink)
+ (void) unlink(ifd_path);
+
+ pe->handled = true;
+
+ return 0;
+}
+
+static int write_dmesg(const char *dmesg, size_t size, const char *id) {
+ _cleanup_(unlink_and_freep) char *tmp_path = NULL;
+ _cleanup_free_ char *ofd_path = NULL;
+ _cleanup_close_ int ofd = -1;
+ ssize_t wr;
+ int r;
+
+ if (size == 0)
+ return 0;
+
+ assert(dmesg);
+
+ ofd_path = path_join(arg_archivedir, id, "dmesg.txt");
+ if (!ofd_path)
+ return log_oom();
+
+ ofd = open_tmpfile_linkable(ofd_path, O_CLOEXEC|O_CREAT|O_TRUNC|O_WRONLY, &tmp_path);
+ if (ofd < 0)
+ return log_error_errno(ofd, "Failed to open temporary file %s: %m", ofd_path);
+ wr = write(ofd, dmesg, size);
+ if (wr < 0)
+ return log_error_errno(errno, "Failed to store dmesg to %s: %m", ofd_path);
+ if (wr != (ssize_t)size)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to store dmesg to %s. %zu bytes are lost.", ofd_path, size - wr);
+ r = link_tmpfile(ofd, tmp_path, ofd_path);
+ if (r < 0)
+ return log_error_errno(r, "Failed to write temporary file %s: %m", ofd_path);
+ tmp_path = mfree(tmp_path);
+
+ return 0;
+}
+
+static void process_dmesg_files(PStoreList *list) {
+ /* Move files, reconstruct dmesg.txt */
+ _cleanup_free_ char *dmesg = NULL, *dmesg_id = NULL;
+ size_t dmesg_size = 0, dmesg_allocated = 0;
+ bool dmesg_bad = false;
+ PStoreEntry *pe;
+
+ /* Handle each dmesg file: files processed in reverse
+ * order so as to properly reconstruct original dmesg */
+ for (size_t n = list->n_entries; n > 0; n--) {
+ bool move_file_and_continue = false;
+ _cleanup_free_ char *pe_id = NULL;
+ char *p;
+ size_t plen;
+
+ pe = &list->entries[n-1];
+
+ if (pe->handled)
+ continue;
+ if (!startswith(pe->dirent.d_name, "dmesg-"))
+ continue;
+
+ if (endswith(pe->dirent.d_name, ".enc.z")) /* indicates a problem */
+ move_file_and_continue = true;
+ p = strrchr(pe->dirent.d_name, '-');
+ if (!p)
+ move_file_and_continue = true;
+
+ if (move_file_and_continue) {
+ /* A dmesg file on which we do NO additional processing */
+ (void) move_file(pe, NULL);
+ continue;
+ }
+
+ /* See if this file is one of a related group of files
+ * in order to reconstruct dmesg */
+
+ /* When dmesg is written into pstore, it is done so in
+ * small chunks, whatever the exchange buffer size is
+ * with the underlying pstore backend (ie. EFI may be
+ * ~2KiB), which means an example pstore with approximately
+ * 64KB of storage may have up to roughly 32 dmesg files
+ * that could be related, depending upon the size of the
+ * original dmesg.
+ *
+ * Here we look at the dmesg filename and try to discern
+ * if files are part of a related group, meaning the same
+ * original dmesg.
+ *
+ * The two known pstore backends are EFI and ERST. These
+ * backends store data in the Common Platform Error
+ * Record, CPER, format. The dmesg- filename contains the
+ * CPER record id, a 64bit number (in decimal notation).
+ * In Linux, the record id is encoded with two digits for
+ * the dmesg part (chunk) number and 3 digits for the
+ * count number. So allowing an additional digit to
+ * compensate for advancing time, this code ignores the
+ * last six digits of the filename in determining the
+ * record id.
+ *
+ * For the EFI backend, the record id encodes an id in the
+ * upper 32 bits, and a timestamp in the lower 32-bits.
+ * So ignoring the least significant 6 digits has proven
+ * to generally identify related dmesg entries. */
+#define PSTORE_FILENAME_IGNORE 6
+
+ /* determine common portion of record id */
+ ++p; /* move beyond dmesg- */
+ plen = strlen(p);
+ if (plen > PSTORE_FILENAME_IGNORE) {
+ pe_id = memdup_suffix0(p, plen - PSTORE_FILENAME_IGNORE);
+ if (!pe_id) {
+ log_oom();
+ return;
+ }
+ } else
+ pe_id = mfree(pe_id);
+
+ /* Now move file from pstore to archive storage */
+ move_file(pe, pe_id);
+
+ if (dmesg_bad)
+ continue;
+
+ /* If the current record id is NOT the same as the
+ * previous record id, then start a new dmesg.txt file */
+ if (!streq_ptr(pe_id, dmesg_id)) {
+ /* Encountered a new dmesg group, close out old one, open new one */
+ (void) write_dmesg(dmesg, dmesg_size, dmesg_id);
+ dmesg_size = 0;
+
+ /* now point dmesg_id to storage of pe_id */
+ free_and_replace(dmesg_id, pe_id);
+ }
+
+ /* Reconstruction of dmesg is done as a useful courtesy: do not fail, but don't write garbled
+ * output either. */
+ size_t needed = strlen(pe->dirent.d_name) + strlen(":\n") + pe->content_size + 1;
+ if (!GREEDY_REALLOC(dmesg, dmesg_allocated, dmesg_size + needed)) {
+ log_oom();
+ dmesg_bad = true;
+ continue;
+ }
+
+ dmesg_size += sprintf(dmesg + dmesg_size, "%s:\n", pe->dirent.d_name);
+ if (pe->content) {
+ memcpy(dmesg + dmesg_size, pe->content, pe->content_size);
+ dmesg_size += pe->content_size;
+ }
+
+ pe_id = mfree(pe_id);
+ }
+
+ if (!dmesg_bad)
+ (void) write_dmesg(dmesg, dmesg_size, dmesg_id);
+}
+
+static int list_files(PStoreList *list, const char *sourcepath) {
+ _cleanup_(closedirp) DIR *dirp = NULL;
+ struct dirent *de;
+ int r;
+
+ dirp = opendir(sourcepath);
+ if (!dirp)
+ return log_error_errno(errno, "Failed to opendir %s: %m", sourcepath);
+
+ FOREACH_DIRENT(de, dirp, return log_error_errno(errno, "Failed to iterate through %s: %m", sourcepath)) {
+ _cleanup_free_ char *ifd_path = NULL;
+
+ ifd_path = path_join(sourcepath, de->d_name);
+ if (!ifd_path)
+ return log_oom();
+
+ _cleanup_free_ char *buf = NULL;
+ size_t buf_size;
+
+ /* Now read contents of pstore file */
+ r = read_full_file(ifd_path, &buf, &buf_size);
+ if (r < 0) {
+ log_warning_errno(r, "Failed to read file %s, skipping: %m", ifd_path);
+ continue;
+ }
+
+ if (!GREEDY_REALLOC(list->entries, list->n_allocated, list->n_entries + 1))
+ return log_oom();
+
+ list->entries[list->n_entries++] = (PStoreEntry) {
+ .dirent = *de,
+ .content = TAKE_PTR(buf),
+ .content_size = buf_size,
+ .is_binary = true,
+ .handled = false,
+ };
+ }
+
+ return 0;
+}
+
+static int run(int argc, char *argv[]) {
+ _cleanup_(pstore_entries_reset) PStoreList list = {};
+ int r;
+
+ log_setup_service();
+
+ if (argc == 3) {
+ arg_sourcedir = argv[1];
+ arg_archivedir = argv[2];
+ } else if (argc > 1)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "This program takes zero or two arguments.");
+
+ /* Ignore all parse errors */
+ (void) parse_config();
+
+ log_debug("Selected storage: %s.", pstore_storage_to_string(arg_storage));
+ log_debug("Selected unlink: %s.", yes_no(arg_unlink));
+
+ if (arg_storage == PSTORE_STORAGE_NONE)
+ /* Do nothing, intentionally, leaving pstore untouched */
+ return 0;
+
+ /* Obtain list of files in pstore */
+ r = list_files(&list, arg_sourcedir);
+ if (r < 0)
+ return r;
+
+ /* Handle each pstore file */
+ /* Sort files lexigraphically ascending, generally needed by all */
+ typesafe_qsort(list.entries, list.n_entries, compare_pstore_entries);
+
+ /* Process known file types */
+ process_dmesg_files(&list);
+
+ /* Move left over files out of pstore */
+ for (size_t n = 0; n < list.n_entries; n++)
+ move_file(&list.entries[n], NULL);
+
+ return 0;
+}
+
+DEFINE_MAIN_FUNCTION(run);