libfs: set SB_I_NOEXEC and SB_I_NODEV by default in init_pseudo()
Summary
| CVE | CVE-2026-64596 |
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-06 08:16:35 UTC |
| Updated | 2026-08-06 08:16:35 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved:
libfs: set SB_I_NOEXEC and SB_I_NODEV by default in init_pseudo()
Since commit 1e7ab6f67824 ("anon_inode: rework assertions"),
path_noexec() warns when an anonymous-inode file is mmap'd from a
superblock that has not set SB_I_NOEXEC. dma-buf backs its files this
way and never set the flag, so mmap of any exported buffer trips the
warning on a CONFIG_DEBUG_VFS=y kernel:
WARNING: CPU: 11 PID: 121813 at fs/exec.c:118 path_noexec+0x47/0x50
do_mmap+0x2b5/0x680
vm_mmap_pgoff+0x129/0x210
ksys_mmap_pgoff+0x177/0x240
__x64_sys_mmap+0x33/0x70
init_pseudo() sets up internal SB_NOUSER mounts that are never
path-reachable. Set both flags here so every pseudo filesystem gets
them by default instead of each caller setting them.
SB_I_NODEV is inert for unreachable mounts. SB_I_NOEXEC has one
visible effect: an executable mapping of a pseudo-fs fd, such as a
dma-buf, now fails with -EPERM, which is the invariant the assertion
enforces. No in-tree caller maps these executable.
Reproduce on CONFIG_DEBUG_VFS=y:
make -C tools/testing/selftests/dmabuf-heaps
sudo ./tools/testing/selftests/dmabuf-heaps/dmabuf-heap -t system |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected 1e7ab6f67824343ee3e96f100f0937c393749a8a b9d45d328fcda4f0d3d281b7d6f12d3f181d9381 git |
Not specified |
| CNA |
Linux |
Linux |
affected 1e7ab6f67824343ee3e96f100f0937c393749a8a 8e931557b317f0fb414839fa51fae1d5feb0ad97 git |
Not specified |
| CNA |
Linux |
Linux |
affected 1e7ab6f67824343ee3e96f100f0937c393749a8a 6de2aeffabaafaeda819e60ec8d04f199711e11a git |
Not specified |
| CNA |
Linux |
Linux |
affected 9b8076a9404568d6cb6673b9a079558b15051966 git |
Not specified |
| CNA |
Linux |
Linux |
affected 6.15.6 6.16 semver |
Not specified |
| CNA |
Linux |
Linux |
affected 6.16 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.16 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18.39 6.18.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.1.4 7.1.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.2-rc1 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/b9d45d328fcda4f0d3d281b7d6f12d3f181d9381 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/6de2aeffabaafaeda819e60ec8d04f199711e11a |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/8e931557b317f0fb414839fa51fae1d5feb0ad97 |
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.