In the Linux kernel, the following vulnerability has been resolved:
kcm: annotate data-races around kcm->rx_psock
kcm->rx_psock can be read locklessly in kcm_rfree().
Annotate the read and writes accordingly.
We do the same for kcm->rx_wait in the following patch.
syzbot reported:
BUG: KCSAN: data-race in kcm_rfree / unreserve_rx_kcm
write to 0xffff888123d827b8 of 8 bytes by task 2758 on cpu 1:
unreserve_rx_kcm+0x72/0x1f0 net/kcm/kcmsock.c:313
kcm_rcv_strparser+0x2b5/0x3a0 net/kcm/kcmsock.c:373
__strp_recv+0x64c/0xd20 net/strparser/strparser.c:301
strp_recv+0x6d/0x80 net/strparser/strparser.c:335
tcp_read_sock+0x13e/0x5a0 net/ipv4/tcp.c:1703
strp_read_sock net/strparser/strparser.c:358 [inline]
do_strp_work net/strparser/strparser.c:406 [inline]
strp_work+0xe8/0x180 net/strparser/strparser.c:415
process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
worker_thread+0x618/0xa70 kernel/workqueue.c:2436
kthread+0x1a9/0x1e0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
read to 0xffff888123d827b8 of 8 bytes by task 5859 on cpu 0:
kcm_rfree+0x14c/0x220 net/kcm/kcmsock.c:181
skb_release_head_state+0x8e/0x160 net/core/skbuff.c:841
skb_release_all net/core/skbuff.c:852 [inline]
__kfree_skb net/core/skbuff.c:868 [inline]
kfree_skb_reason+0x5c/0x260 net/core/skbuff.c:891
kfree_skb include/linux/skbuff.h:1216 [inline]
kcm_recvmsg+0x226/0x2b0 net/kcm/kcmsock.c:1161
____sys_recvmsg+0x16c/0x2e0
___sys_recvmsg net/socket.c:2743 [inline]
do_recvmmsg+0x2f1/0x710 net/socket.c:2837
__sys_recvmmsg net/socket.c:2916 [inline]
__do_sys_recvmmsg net/socket.c:2939 [inline]
__se_sys_recvmmsg net/socket.c:2932 [inline]
__x64_sys_recvmmsg+0xde/0x160 net/socket.c:2932
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
value changed: 0xffff88812971ce00 -> 0x0000000000000000
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5859 Comm: syz-executor.3 Not tainted 6.0.0-syzkaller-12189-g19d17ab7c68b-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Metrics
Affected Vendors & Products
| Vendors | Products |
|---|---|
| Linux |
|
No data.
No data.
References
History
Wed, 17 Sep 2025 11:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
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| Vendors & Products |
Linux
Linux linux Kernel |
Tue, 16 Sep 2025 00:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
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| Metrics |
threat_severity
|
cvssV3_1
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Mon, 15 Sep 2025 15:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: kcm: annotate data-races around kcm->rx_psock kcm->rx_psock can be read locklessly in kcm_rfree(). Annotate the read and writes accordingly. We do the same for kcm->rx_wait in the following patch. syzbot reported: BUG: KCSAN: data-race in kcm_rfree / unreserve_rx_kcm write to 0xffff888123d827b8 of 8 bytes by task 2758 on cpu 1: unreserve_rx_kcm+0x72/0x1f0 net/kcm/kcmsock.c:313 kcm_rcv_strparser+0x2b5/0x3a0 net/kcm/kcmsock.c:373 __strp_recv+0x64c/0xd20 net/strparser/strparser.c:301 strp_recv+0x6d/0x80 net/strparser/strparser.c:335 tcp_read_sock+0x13e/0x5a0 net/ipv4/tcp.c:1703 strp_read_sock net/strparser/strparser.c:358 [inline] do_strp_work net/strparser/strparser.c:406 [inline] strp_work+0xe8/0x180 net/strparser/strparser.c:415 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289 worker_thread+0x618/0xa70 kernel/workqueue.c:2436 kthread+0x1a9/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 read to 0xffff888123d827b8 of 8 bytes by task 5859 on cpu 0: kcm_rfree+0x14c/0x220 net/kcm/kcmsock.c:181 skb_release_head_state+0x8e/0x160 net/core/skbuff.c:841 skb_release_all net/core/skbuff.c:852 [inline] __kfree_skb net/core/skbuff.c:868 [inline] kfree_skb_reason+0x5c/0x260 net/core/skbuff.c:891 kfree_skb include/linux/skbuff.h:1216 [inline] kcm_recvmsg+0x226/0x2b0 net/kcm/kcmsock.c:1161 ____sys_recvmsg+0x16c/0x2e0 ___sys_recvmsg net/socket.c:2743 [inline] do_recvmmsg+0x2f1/0x710 net/socket.c:2837 __sys_recvmmsg net/socket.c:2916 [inline] __do_sys_recvmmsg net/socket.c:2939 [inline] __se_sys_recvmmsg net/socket.c:2932 [inline] __x64_sys_recvmmsg+0xde/0x160 net/socket.c:2932 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0xffff88812971ce00 -> 0x0000000000000000 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 5859 Comm: syz-executor.3 Not tainted 6.0.0-syzkaller-12189-g19d17ab7c68b-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 | |
| Title | kcm: annotate data-races around kcm->rx_psock | |
| References |
|
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published: 2025-09-15T14:45:47.510Z
Updated: 2025-09-15T14:45:47.510Z
Reserved: 2025-09-15T14:18:36.811Z
Link: CVE-2022-50291
Vulnrichment
No data.
NVD
Status : Awaiting Analysis
Published: 2025-09-15T15:15:40.400
Modified: 2025-09-15T15:22:27.090
Link: CVE-2022-50291
Redhat