diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
| commit | 034dd340b08be1f2f0477ad16131d609f9dbd53c (patch) | |
| tree | 2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /net/compat.c | |
| download | linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip | |
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt:
- Fix error output of boot instance creation failure
Currently if a boot instance creation fails, instead of printing out
the name of the instance that failed, it prints "(null)". That is
because it prints "cur_str" that had already been processed by
strsep(). Print the saved name instead.
While at it, print the error code of the failure.
- Fix use-after-free for same named historgrams
Histograms can be named so that they can be used in multiple events.
But if the named histogram has a variable attached, the second event
that uses the named histogram which duplicates it and needs to free
the original after duplication leaves the old variable in place and
still visible. If another histogram uses than variable, it will use
the stale one which will try to reference the freed duplicate
histogram and crash the kernel.
Free the duplicate variables along with the duplicated histogram
data.
- Check return value of kthread_run() in event self test
The events self tests uses a kthread for testing but does not check
if it succeeded in creating a kthread. If the kthread creation were
to fail, the code will still try to call kthread_stop() on the error
returned.
- Fix race between reading trace_pipe and updating subbuffer size
If a user is reading the trace_pipe file at the same time they update
the ring buffer sub-buffer size, can cause the trace_pipe read to
read stale data. Add trace_access_lock() around updating the ring
buffer sub-buffer size.
- Fix eventfs_inode on failure path in creation of the events directory
In the creation of the "events" directory, if after allocating the
eventfs_inode a failure is detected, it calls cleanup_ei() which
calls free_ei(). The free_ei() will test if eventfs_inode being freed
has no children. It is a bug if it does. But on the failure case of
the creation of the "events" directory, the children lists have not
yet been initialized and the free will trigger a warning because
list_empty() on an uninitialized list returns false.
Move the initialization into init_ei() where it makes more sense and
makes sure that a created eventfs_inode has its lists initialized
upon creation.
- Check return value of kthread_run() in ftrace direct sample code
The sample code that shows how to use the ftrace direct calls does
not test the return of kthread_run() to see if it succeeds. Return a
failure if the kthread_run() doesn't succeed.
- Clear user events state on fork in case of alloc failure
On fork, the child gets a pointer to the parent's user events state.
It makes a copy of it then updates the child's pointer to it. But if
the allocation fails, the duplication function leaves the child with
a pointer to its parent's descriptor. When the child cleans up its
data, it will free the parent's descriptor while the parent is still
using it.
In the duplication function, set the child's user_event_mm to NULL
before testing if the allocation succeeded, and when it exits it will
not free the parent's descriptor.
- Fix retry exhaustion in simple ring buffer reader swap
simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
post-decrements it only after a failed link replacement. On the final
attempt, a successful replacement leaves retry at zero, while a
failed replacement leaves it at -1.
But the check for success expects the retry value to be non-zero and
exits with an error on zero. This is the opposite result. Fix it.
- Fail nicely when the remote swap_reader_page() returns an error
Currently, if the swap_reader_page() of a remote buffer fails, it
triggers a WARN_ON_ONCE() and continues normally. Instead, have it
exit with an error and a pr_warn() print instead of a full WARNING.
* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Stop remote reader update when page swap fails
tracing: Fix retry exhaustion in simple ring buffer reader swap
tracing/user_events: Clear copied tracing state before fork duplication
samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
eventfs: Initialize ei->children and ei->list in init_ei()
tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
tracing: Fix crash passing ERR_PTR to kthread_stop()
tracing: Fix use-after-free with same-name named triggers
tracing: Fix logged instance name on creation failure
Diffstat (limited to 'net/compat.c')
| -rw-r--r-- | net/compat.c | 518 |
1 files changed, 518 insertions, 0 deletions
diff --git a/net/compat.c b/net/compat.c new file mode 100644 index 000000000..6bdf4a2c9 --- /dev/null +++ b/net/compat.c @@ -0,0 +1,518 @@ +// 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 *msg, + struct sockaddr __user **save_addr) +{ + ssize_t err; + + 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_get_inq = 0; + 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_ubuf = NULL; + return 0; +} + +int get_compat_msghdr(struct msghdr *kmsg, + struct compat_msghdr __user *umsg, + struct sockaddr __user **save_addr, + struct iovec **iov) +{ + struct compat_msghdr msg; + ssize_t err; + + if (copy_from_user(&msg, umsg, sizeof(*umsg))) + return -EFAULT; + + err = __get_compat_msghdr(kmsg, &msg, save_addr); + if (err) + return err; + + err = import_iovec(save_addr ? ITER_DEST : ITER_SOURCE, + compat_ptr(msg.msg_iov), msg.msg_iovlen, + 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_user) : \ + (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_user) > + 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_is_user = false; + 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_user; + 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_user += 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, bool notrunc) +{ + struct compat_cmsghdr __user *cm = + (struct compat_cmsghdr __user *)msg->msg_control_user; + 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 = scm_recv_one_fd(scm->fp->fp[i], cmsg_data + i, o_flags, notrunc); + 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_user += 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]), 0); + break; + case SYS_GETPEERNAME: + ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]), 1); + 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; +} |
