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-rw-r--r--net/compat.c520
1 files changed, 520 insertions, 0 deletions
diff --git a/net/compat.c b/net/compat.c
new file mode 100644
index 000000000..210fc3b4d
--- /dev/null
+++ b/net/compat.c
@@ -0,0 +1,520 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 32bit Socket syscall emulation. Based on arch/sparc64/kernel/sys_sparc32.c.
+ *
+ * Copyright (C) 2000 VA Linux Co
+ * Copyright (C) 2000 Don Dugger <n0ano@valinux.com>
+ * Copyright (C) 1999 Arun Sharma <arun.sharma@intel.com>
+ * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 2000 Hewlett-Packard Co.
+ * Copyright (C) 2000 David Mosberger-Tang <davidm@hpl.hp.com>
+ * Copyright (C) 2000,2001 Andi Kleen, SuSE Labs
+ */
+
+#include <linux/kernel.h>
+#include <linux/gfp.h>
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/file.h>
+#include <linux/icmpv6.h>
+#include <linux/socket.h>
+#include <linux/syscalls.h>
+#include <linux/filter.h>
+#include <linux/compat.h>
+#include <linux/security.h>
+#include <linux/audit.h>
+#include <linux/export.h>
+
+#include <net/scm.h>
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <linux/uaccess.h>
+#include <net/compat.h>
+
+int __get_compat_msghdr(struct msghdr *kmsg,
+ struct compat_msghdr __user *umsg,
+ struct sockaddr __user **save_addr,
+ compat_uptr_t *ptr, compat_size_t *len)
+{
+ struct compat_msghdr msg;
+ ssize_t err;
+
+ if (copy_from_user(&msg, umsg, sizeof(*umsg)))
+ return -EFAULT;
+
+ kmsg->msg_flags = msg.msg_flags;
+ kmsg->msg_namelen = msg.msg_namelen;
+
+ if (!msg.msg_name)
+ kmsg->msg_namelen = 0;
+
+ if (kmsg->msg_namelen < 0)
+ return -EINVAL;
+
+ if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
+ kmsg->msg_namelen = sizeof(struct sockaddr_storage);
+
+ kmsg->msg_control_is_user = true;
+ kmsg->msg_control_user = compat_ptr(msg.msg_control);
+ kmsg->msg_controllen = msg.msg_controllen;
+
+ if (save_addr)
+ *save_addr = compat_ptr(msg.msg_name);
+
+ if (msg.msg_name && kmsg->msg_namelen) {
+ if (!save_addr) {
+ err = move_addr_to_kernel(compat_ptr(msg.msg_name),
+ kmsg->msg_namelen,
+ kmsg->msg_name);
+ if (err < 0)
+ return err;
+ }
+ } else {
+ kmsg->msg_name = NULL;
+ kmsg->msg_namelen = 0;
+ }
+
+ if (msg.msg_iovlen > UIO_MAXIOV)
+ return -EMSGSIZE;
+
+ kmsg->msg_iocb = NULL;
+ *ptr = msg.msg_iov;
+ *len = msg.msg_iovlen;
+ return 0;
+}
+
+int get_compat_msghdr(struct msghdr *kmsg,
+ struct compat_msghdr __user *umsg,
+ struct sockaddr __user **save_addr,
+ struct iovec **iov)
+{
+ compat_uptr_t ptr;
+ compat_size_t len;
+ ssize_t err;
+
+ err = __get_compat_msghdr(kmsg, umsg, save_addr, &ptr, &len);
+ if (err)
+ return err;
+
+ err = import_iovec(save_addr ? READ : WRITE, compat_ptr(ptr), len,
+ UIO_FASTIOV, iov, &kmsg->msg_iter);
+ return err < 0 ? err : 0;
+}
+
+/* Bleech... */
+#define CMSG_COMPAT_ALIGN(len) ALIGN((len), sizeof(s32))
+
+#define CMSG_COMPAT_DATA(cmsg) \
+ ((void __user *)((char __user *)(cmsg) + sizeof(struct compat_cmsghdr)))
+#define CMSG_COMPAT_SPACE(len) \
+ (sizeof(struct compat_cmsghdr) + CMSG_COMPAT_ALIGN(len))
+#define CMSG_COMPAT_LEN(len) \
+ (sizeof(struct compat_cmsghdr) + (len))
+
+#define CMSG_COMPAT_FIRSTHDR(msg) \
+ (((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ? \
+ (struct compat_cmsghdr __user *)((msg)->msg_control) : \
+ (struct compat_cmsghdr __user *)NULL)
+
+#define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
+ ((ucmlen) >= sizeof(struct compat_cmsghdr) && \
+ (ucmlen) <= (unsigned long) \
+ ((mhdr)->msg_controllen - \
+ ((char __user *)(ucmsg) - (char __user *)(mhdr)->msg_control_user)))
+
+static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
+ struct compat_cmsghdr __user *cmsg, int cmsg_len)
+{
+ char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
+ if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) >
+ msg->msg_controllen)
+ return NULL;
+ return (struct compat_cmsghdr __user *)ptr;
+}
+
+/* There is a lot of hair here because the alignment rules (and
+ * thus placement) of cmsg headers and length are different for
+ * 32-bit apps. -DaveM
+ */
+int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
+ unsigned char *stackbuf, int stackbuf_size)
+{
+ struct compat_cmsghdr __user *ucmsg;
+ struct cmsghdr *kcmsg, *kcmsg_base;
+ compat_size_t ucmlen;
+ __kernel_size_t kcmlen, tmp;
+ int err = -EFAULT;
+
+ BUILD_BUG_ON(sizeof(struct compat_cmsghdr) !=
+ CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)));
+
+ kcmlen = 0;
+ kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
+ ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
+ while (ucmsg != NULL) {
+ if (get_user(ucmlen, &ucmsg->cmsg_len))
+ return -EFAULT;
+
+ /* Catch bogons. */
+ if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
+ return -EINVAL;
+
+ tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
+ tmp = CMSG_ALIGN(tmp);
+ kcmlen += tmp;
+ ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
+ }
+ if (kcmlen == 0)
+ return -EINVAL;
+
+ /* The kcmlen holds the 64-bit version of the control length.
+ * It may not be modified as we do not stick it into the kmsg
+ * until we have successfully copied over all of the data
+ * from the user.
+ */
+ if (kcmlen > stackbuf_size)
+ kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
+ if (kcmsg == NULL)
+ return -ENOMEM;
+
+ /* Now copy them over neatly. */
+ memset(kcmsg, 0, kcmlen);
+ ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
+ while (ucmsg != NULL) {
+ struct compat_cmsghdr cmsg;
+ if (copy_from_user(&cmsg, ucmsg, sizeof(cmsg)))
+ goto Efault;
+ if (!CMSG_COMPAT_OK(cmsg.cmsg_len, ucmsg, kmsg))
+ goto Einval;
+ tmp = ((cmsg.cmsg_len - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
+ if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
+ goto Einval;
+ kcmsg->cmsg_len = tmp;
+ kcmsg->cmsg_level = cmsg.cmsg_level;
+ kcmsg->cmsg_type = cmsg.cmsg_type;
+ tmp = CMSG_ALIGN(tmp);
+ if (copy_from_user(CMSG_DATA(kcmsg),
+ CMSG_COMPAT_DATA(ucmsg),
+ (cmsg.cmsg_len - sizeof(*ucmsg))))
+ goto Efault;
+
+ /* Advance. */
+ kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
+ ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, cmsg.cmsg_len);
+ }
+
+ /*
+ * check the length of messages copied in is the same as the
+ * what we get from the first loop
+ */
+ if ((char *)kcmsg - (char *)kcmsg_base != kcmlen)
+ goto Einval;
+
+ /* Ok, looks like we made it. Hook it up and return success. */
+ kmsg->msg_control = kcmsg_base;
+ kmsg->msg_controllen = kcmlen;
+ return 0;
+
+Einval:
+ err = -EINVAL;
+Efault:
+ if (kcmsg_base != (struct cmsghdr *)stackbuf)
+ sock_kfree_s(sk, kcmsg_base, kcmlen);
+ return err;
+}
+
+int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
+{
+ struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
+ struct compat_cmsghdr cmhdr;
+ struct old_timeval32 ctv;
+ struct old_timespec32 cts[3];
+ int cmlen;
+
+ if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
+ kmsg->msg_flags |= MSG_CTRUNC;
+ return 0; /* XXX: return error? check spec. */
+ }
+
+ if (!COMPAT_USE_64BIT_TIME) {
+ if (level == SOL_SOCKET && type == SO_TIMESTAMP_OLD) {
+ struct __kernel_old_timeval *tv = (struct __kernel_old_timeval *)data;
+ ctv.tv_sec = tv->tv_sec;
+ ctv.tv_usec = tv->tv_usec;
+ data = &ctv;
+ len = sizeof(ctv);
+ }
+ if (level == SOL_SOCKET &&
+ (type == SO_TIMESTAMPNS_OLD || type == SO_TIMESTAMPING_OLD)) {
+ int count = type == SO_TIMESTAMPNS_OLD ? 1 : 3;
+ int i;
+ struct __kernel_old_timespec *ts = data;
+ for (i = 0; i < count; i++) {
+ cts[i].tv_sec = ts[i].tv_sec;
+ cts[i].tv_nsec = ts[i].tv_nsec;
+ }
+ data = &cts;
+ len = sizeof(cts[0]) * count;
+ }
+ }
+
+ cmlen = CMSG_COMPAT_LEN(len);
+ if (kmsg->msg_controllen < cmlen) {
+ kmsg->msg_flags |= MSG_CTRUNC;
+ cmlen = kmsg->msg_controllen;
+ }
+ cmhdr.cmsg_level = level;
+ cmhdr.cmsg_type = type;
+ cmhdr.cmsg_len = cmlen;
+
+ if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
+ return -EFAULT;
+ if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
+ return -EFAULT;
+ cmlen = CMSG_COMPAT_SPACE(len);
+ if (kmsg->msg_controllen < cmlen)
+ cmlen = kmsg->msg_controllen;
+ kmsg->msg_control += cmlen;
+ kmsg->msg_controllen -= cmlen;
+ return 0;
+}
+
+static int scm_max_fds_compat(struct msghdr *msg)
+{
+ if (msg->msg_controllen <= sizeof(struct compat_cmsghdr))
+ return 0;
+ return (msg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
+}
+
+void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm)
+{
+ struct compat_cmsghdr __user *cm =
+ (struct compat_cmsghdr __user *)msg->msg_control;
+ unsigned int o_flags = (msg->msg_flags & MSG_CMSG_CLOEXEC) ? O_CLOEXEC : 0;
+ int fdmax = min_t(int, scm_max_fds_compat(msg), scm->fp->count);
+ int __user *cmsg_data = CMSG_COMPAT_DATA(cm);
+ int err = 0, i;
+
+ for (i = 0; i < fdmax; i++) {
+ err = receive_fd_user(scm->fp->fp[i], cmsg_data + i, o_flags);
+ if (err < 0)
+ break;
+ }
+
+ if (i > 0) {
+ int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
+
+ err = put_user(SOL_SOCKET, &cm->cmsg_level);
+ if (!err)
+ err = put_user(SCM_RIGHTS, &cm->cmsg_type);
+ if (!err)
+ err = put_user(cmlen, &cm->cmsg_len);
+ if (!err) {
+ cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
+ if (msg->msg_controllen < cmlen)
+ cmlen = msg->msg_controllen;
+ msg->msg_control += cmlen;
+ msg->msg_controllen -= cmlen;
+ }
+ }
+
+ if (i < scm->fp->count || (scm->fp->count && fdmax <= 0))
+ msg->msg_flags |= MSG_CTRUNC;
+
+ /*
+ * All of the files that fit in the message have had their usage counts
+ * incremented, so we just free the list.
+ */
+ __scm_destroy(scm);
+}
+
+/* Argument list sizes for compat_sys_socketcall */
+#define AL(x) ((x) * sizeof(u32))
+static unsigned char nas[21] = {
+ AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
+ AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
+ AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
+ AL(4), AL(5), AL(4)
+};
+#undef AL
+
+static inline long __compat_sys_sendmsg(int fd,
+ struct compat_msghdr __user *msg,
+ unsigned int flags)
+{
+ return __sys_sendmsg(fd, (struct user_msghdr __user *)msg,
+ flags | MSG_CMSG_COMPAT, false);
+}
+
+COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg,
+ unsigned int, flags)
+{
+ return __compat_sys_sendmsg(fd, msg, flags);
+}
+
+static inline long __compat_sys_sendmmsg(int fd,
+ struct compat_mmsghdr __user *mmsg,
+ unsigned int vlen, unsigned int flags)
+{
+ return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
+ flags | MSG_CMSG_COMPAT, false);
+}
+
+COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
+ unsigned int, vlen, unsigned int, flags)
+{
+ return __compat_sys_sendmmsg(fd, mmsg, vlen, flags);
+}
+
+static inline long __compat_sys_recvmsg(int fd,
+ struct compat_msghdr __user *msg,
+ unsigned int flags)
+{
+ return __sys_recvmsg(fd, (struct user_msghdr __user *)msg,
+ flags | MSG_CMSG_COMPAT, false);
+}
+
+COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg,
+ unsigned int, flags)
+{
+ return __compat_sys_recvmsg(fd, msg, flags);
+}
+
+static inline long __compat_sys_recvfrom(int fd, void __user *buf,
+ compat_size_t len, unsigned int flags,
+ struct sockaddr __user *addr,
+ int __user *addrlen)
+{
+ return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr,
+ addrlen);
+}
+
+COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
+{
+ return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL);
+}
+
+COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
+ unsigned int, flags, struct sockaddr __user *, addr,
+ int __user *, addrlen)
+{
+ return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen);
+}
+
+COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg,
+ unsigned int, vlen, unsigned int, flags,
+ struct __kernel_timespec __user *, timeout)
+{
+ return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
+ flags | MSG_CMSG_COMPAT, timeout, NULL);
+}
+
+#ifdef CONFIG_COMPAT_32BIT_TIME
+COMPAT_SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct compat_mmsghdr __user *, mmsg,
+ unsigned int, vlen, unsigned int, flags,
+ struct old_timespec32 __user *, timeout)
+{
+ return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
+ flags | MSG_CMSG_COMPAT, NULL, timeout);
+}
+#endif
+
+COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
+{
+ u32 a[AUDITSC_ARGS];
+ unsigned int len;
+ u32 a0, a1;
+ int ret;
+
+ if (call < SYS_SOCKET || call > SYS_SENDMMSG)
+ return -EINVAL;
+ len = nas[call];
+ if (len > sizeof(a))
+ return -EINVAL;
+
+ if (copy_from_user(a, args, len))
+ return -EFAULT;
+
+ ret = audit_socketcall_compat(len / sizeof(a[0]), a);
+ if (ret)
+ return ret;
+
+ a0 = a[0];
+ a1 = a[1];
+
+ switch (call) {
+ case SYS_SOCKET:
+ ret = __sys_socket(a0, a1, a[2]);
+ break;
+ case SYS_BIND:
+ ret = __sys_bind(a0, compat_ptr(a1), a[2]);
+ break;
+ case SYS_CONNECT:
+ ret = __sys_connect(a0, compat_ptr(a1), a[2]);
+ break;
+ case SYS_LISTEN:
+ ret = __sys_listen(a0, a1);
+ break;
+ case SYS_ACCEPT:
+ ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
+ break;
+ case SYS_GETSOCKNAME:
+ ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
+ break;
+ case SYS_GETPEERNAME:
+ ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
+ break;
+ case SYS_SOCKETPAIR:
+ ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
+ break;
+ case SYS_SEND:
+ ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0);
+ break;
+ case SYS_SENDTO:
+ ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3],
+ compat_ptr(a[4]), a[5]);
+ break;
+ case SYS_RECV:
+ ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
+ NULL, NULL);
+ break;
+ case SYS_RECVFROM:
+ ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
+ compat_ptr(a[4]),
+ compat_ptr(a[5]));
+ break;
+ case SYS_SHUTDOWN:
+ ret = __sys_shutdown(a0, a1);
+ break;
+ case SYS_SETSOCKOPT:
+ ret = __sys_setsockopt(a0, a1, a[2], compat_ptr(a[3]), a[4]);
+ break;
+ case SYS_GETSOCKOPT:
+ ret = __sys_getsockopt(a0, a1, a[2], compat_ptr(a[3]),
+ compat_ptr(a[4]));
+ break;
+ case SYS_SENDMSG:
+ ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
+ break;
+ case SYS_SENDMMSG:
+ ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
+ break;
+ case SYS_RECVMSG:
+ ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
+ break;
+ case SYS_RECVMMSG:
+ ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2],
+ a[3] | MSG_CMSG_COMPAT, NULL,
+ compat_ptr(a[4]));
+ break;
+ case SYS_ACCEPT4:
+ ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ return ret;
+}