net/atm: fix slab-out-of-bounds read in vcc_setsockopt()
Summary
| CVE | CVE-2026-74689 |
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| State | PUBLISHED |
|---|
| Assigner | Linux |
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| Source Priority | CVE Program / NVD first with legacy fallback |
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| Published | 2026-08-22 16:16:43 UTC |
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| Updated | 2026-08-22 16:16:43 UTC |
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| Description | In the Linux kernel, the following vulnerability has been resolved:
net/atm: fix slab-out-of-bounds read in vcc_setsockopt()
vcc_setsockopt() contained an ineffective optlen check:
if (__SO_LEVEL_MATCH(optname, level) && optlen != __SO_SIZE(optname))
return -EINVAL;
If __SO_LEVEL_MATCH(optname, level) evaluated to false (e.g. if the caller
passed a mismatched level), the length check optlen != __SO_SIZE(optname)
was short-circuited and bypassed. Execution then fell through to switch(optname),
calling copy_from_sockptr() assuming optval contained sufficient space.
Furthermore, even if level matched, a cgroup BPF setsockopt filter could shrink
optlen after entry. Because copy_from_sockptr() on kernel pointers uses memcpy(),
this leads to a KASAN slab-out-of-bounds read when optlen is smaller than the
expected structure size.
Fix this by using copy_safe_from_sockptr(), which unconditionally validates
that optlen is at least the expected size before copying. Also change the local
'value' variable type from 'unsigned long' to 'int' so that SO_SETCLP matches
its sizeof(int) ABI encoding on 64-bit systems. |
|---|
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 b3bcd5d65ac03c15787b2a5b36c718e26a689336 git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 35f258fee9ed358c6d0f57f91c30bf029c3724af git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 6eb6af88710977eb529b558a07294874d8c40c4d git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 9f77c1ab382188f5b51982fab6d913443b6dc59f git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 2c5988c7349c0b64a7e0441bfc6e1dca54f7116a git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 d0c80dbb970439bd2eeb0e5effff8c16a5f4e1e3 git |
Not specified |
| CNA |
Linux |
Linux |
affected 2.6.12 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 2.6.12 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.1.183 6.1.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.6.152 6.6.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.12.104 6.12.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18.45 6.18.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.1.9 7.1.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.2 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/9f77c1ab382188f5b51982fab6d913443b6dc59f |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/35f258fee9ed358c6d0f57f91c30bf029c3724af |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/2c5988c7349c0b64a7e0441bfc6e1dca54f7116a |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/6eb6af88710977eb529b558a07294874d8c40c4d |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/d0c80dbb970439bd2eeb0e5effff8c16a5f4e1e3 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/b3bcd5d65ac03c15787b2a5b36c718e26a689336 |
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.