net/smc: avoid NULL deref of conn->lnk in smc_msg_event tracepoint
Summary
| CVE | CVE-2026-52941 |
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-06-24 08:16:24 UTC |
| Updated | 2026-06-24 08:16:24 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved:
net/smc: avoid NULL deref of conn->lnk in smc_msg_event tracepoint
The smc_msg_event tracepoint class, shared by smc_tx_sendmsg and
smc_rx_recvmsg, unconditionally dereferences smc->conn.lnk:
__string(name, smc->conn.lnk->ibname)
conn->lnk is only set for SMC-R; for SMC-D it is NULL. Other code on
these paths already handles this (e.g. !conn->lnk in
SMC_STAT_RMB_TX_SIZE_SMALL()). With the tracepoint enabled, the first
sendmsg()/recvmsg() on an SMC-D socket crashes:
Oops: general protection fault, probably for non-canonical address
KASAN: null-ptr-deref in range [...]
RIP: 0010:strlen+0x1e/0xa0
Call Trace:
trace_event_raw_event_smc_msg_event (net/smc/smc_tracepoint.h:44)
smc_rx_recvmsg (net/smc/smc_rx.c:515)
smc_recvmsg (net/smc/af_smc.c:2859)
__sys_recvfrom (net/socket.c:2315)
__x64_sys_recvfrom (net/socket.c:2326)
do_syscall_64
The faulting address 0x3e0 is offsetof(struct smc_link, ibname),
confirming the NULL ->lnk deref. Enabling the tracepoint requires
root, but the trigger itself is unprivileged: socket(AF_SMC, ...) has
no capability check, and SMC-D negotiation needs no admin step on
s390 or on x86 with the loopback ISM device loaded.
Log an empty device name for SMC-D instead of dereferencing NULL. |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected aff3083f10bff7a37eaa2b4e6bc5fb627ddd5f84 68200112534bb2acd1d7117dc2d5c124868d866d git |
Not specified |
| CNA |
Linux |
Linux |
affected aff3083f10bff7a37eaa2b4e6bc5fb627ddd5f84 720c76b930c52cd58f50eb6b10569d03dccc7959 git |
Not specified |
| CNA |
Linux |
Linux |
affected aff3083f10bff7a37eaa2b4e6bc5fb627ddd5f84 b706d6d76a2a2793fe5ad0fbc2a75b6a460094ef git |
Not specified |
| CNA |
Linux |
Linux |
affected aff3083f10bff7a37eaa2b4e6bc5fb627ddd5f84 d2ea0b8aef8746e147602eac87ca8538f4bc7e66 git |
Not specified |
| CNA |
Linux |
Linux |
affected aff3083f10bff7a37eaa2b4e6bc5fb627ddd5f84 561cf66fa9b6c86dfe4e687d2d1aeaaa6739917f git |
Not specified |
| CNA |
Linux |
Linux |
affected aff3083f10bff7a37eaa2b4e6bc5fb627ddd5f84 7bf563badd37cb796df5477d2b78bb64148a1268 git |
Not specified |
| CNA |
Linux |
Linux |
affected 5.16 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.16 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.1.175 6.1.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.6.142 6.6.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.12.92 6.12.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18.34 6.18.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.0.11 7.0.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.1 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/720c76b930c52cd58f50eb6b10569d03dccc7959 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/68200112534bb2acd1d7117dc2d5c124868d866d |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/d2ea0b8aef8746e147602eac87ca8538f4bc7e66 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/b706d6d76a2a2793fe5ad0fbc2a75b6a460094ef |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/561cf66fa9b6c86dfe4e687d2d1aeaaa6739917f |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/7bf563badd37cb796df5477d2b78bb64148a1268 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| CVE Program record |
CVE.ORG |
www.cve.org |
canonical |
| NVD vulnerability detail |
NVD |
nvd.nist.gov |
canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.