Updated: 2025-12-14 03:53:27.33302
Description:
In the Linux kernel, the following vulnerability has been resolved: af_unix: Fix data-races around user->unix_inflight. user->unix_inflight is changed under spin_lock(unix_gc_lock), but too_many_unix_fds() reads it locklessly. Let's annotate the write/read accesses to user->unix_inflight. BUG: KCSAN: data-race in unix_attach_fds / unix_inflight write to 0xffffffff8546f2d0 of 8 bytes by task 44798 on cpu 1: unix_inflight+0x157/0x180 net/unix/scm.c:66 unix_attach_fds+0x147/0x1e0 net/unix/scm.c:123 unix_scm_to_skb net/unix/af_unix.c:1827 [inline] unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950 unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline] unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg+0x148/0x160 net/socket.c:748 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2494 ___sys_sendmsg+0xc6/0x140 net/socket.c:2548 __sys_sendmsg+0x94/0x140 net/socket.c:2577 __do_sys_sendmsg net/socket.c:2586 [inline] __se_sys_sendmsg net/socket.c:2584 [inline] __x64_sys_sendmsg+0x45/0x50 net/socket.c:2584 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 read to 0xffffffff8546f2d0 of 8 bytes by task 44814 on cpu 0: too_many_unix_fds net/unix/scm.c:101 [inline] unix_attach_fds+0x54/0x1e0 net/unix/scm.c:110 unix_scm_to_skb net/unix/af_unix.c:1827 [inline] unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950 unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline] unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg+0x148/0x160 net/socket.c:748 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2494 ___sys_sendmsg+0xc6/0x140 net/socket.c:2548 __sys_sendmsg+0x94/0x140 net/socket.c:2577 __do_sys_sendmsg net/socket.c:2586 [inline] __se_sys_sendmsg net/socket.c:2584 [inline] __x64_sys_sendmsg+0x45/0x50 net/socket.c:2584 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 value changed: 0x000000000000000c -> 0x000000000000000d Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 44814 Comm: systemd-coredum Not tainted 6.4.0-11989-g6843306689af #6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
| Links | NIST | CIRCL | RHEL | Ubuntu |
| Severity | Score | |
|---|---|---|
| CVSS Version 2.x | 0.0 | |
| CVSS Version 3.x | MEDIUM | 4.7 |
| OS name | Project name | Version | Score | Severity | Status | Errata | Last updated | Statement |
|---|---|---|---|---|---|---|---|---|
| AlmaLinux 9.2 ESU | kernel | 5.14.0 | 4.7 | MEDIUM | Released | CLSA-2025:1764151168 | 2025-11-27 10:25:19 | |
| CentOS 8.4 ELS | kernel | 4.18.0 | 4.7 | MEDIUM | Ignored | 2025-12-18 19:38:19 | ||
| CentOS 8.5 ELS | kernel | 4.18.0 | 4.7 | MEDIUM | Ignored | 2025-12-18 19:38:19 | ||
| Ubuntu 16.04 ELS | linux-hwe | 4.15.0 | 4.7 | MEDIUM | Ignored | 2026-01-16 09:27:20 | Low priority: this is a local-only race condition in AF_UNIX file‑descriptor passing that requires... | |
| Ubuntu 16.04 ELS | linux | 4.4.0 | 4.7 | MEDIUM | Ignored | 2026-01-16 09:25:37 | Low priority: this is a local-only race condition in AF_UNIX file‑descriptor passing that requires... | |
| Ubuntu 18.04 ELS | linux | 4.15.0 | 4.7 | MEDIUM | Ignored | 2026-01-16 09:25:38 | Low priority: this is a local-only race condition in AF_UNIX file‑descriptor passing that requires... |