Description
In the Linux kernel, the following vulnerability has been resolved: NFSD: Hold net reference for the lifetime of /proc/fs/nfs/exports fd The /proc/fs/nfs/exports proc entry is created at module init and persists for the module's lifetime. exports_proc_open() captures the caller's current network namespace and stores its svc_export_cache in seq->private, but takes no reference on the namespace. If the namespace is subsequently torn down (e.g. container destruction after the opener does setns() to a different namespace), nfsd_net_exit() calls nfsd_export_shutdown() which frees the cache. Subsequent reads on the still-open fd dereference the freed cache_detail, walking a freed hash table. Hold a reference on the struct net for the lifetime of the open file descriptor. This prevents nfsd_net_exit() from running -- and thus prevents nfsd_export_shutdown() from freeing the cache -- while any exports fd is open. cache_detail already stores its net pointer (cd->net, set by cache_create_net()), so exports_release() can retrieve it without additional per-file storage.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 to < 76740c28050dc6db2f5550f1325b00a11bbb3255affected96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 to < c7f406fb341d6747634b8b1fa5461656e5e56076affected96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 to < d1a19217995df9c7e4118f5a2820c5032fef2945affected96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 to < e3d77f935639e6ae4b381c80464c31df998d61f4affected96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 to < db4a9f99b12a7ee1c19d86c83a3b752c7effa6c6affected96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 to < 6a8d70e2ad6aad2c345a5048edcb8168036f97d6affected96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 to < e7fcf179b82d3a3730fd8615da01b087cc654d0baffected
Linux Linux
Default version status: affected
3.9affected0 to < 3.9unaffected5.10.253 to ≤ 5.10.*unaffected6.1.167 to ≤ 6.1.*unaffected6.6.130 to ≤ 6.6.*unaffected6.12.78 to ≤ 6.12.*unaffected6.18.20 to ≤ 6.18.*unaffected6.19.10 to ≤ 6.19.*unaffected7.0 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/76740c28050dc6db2f5550f1325b00a11bbb3255 ↗
- https://git.kernel.org/stable/c/c7f406fb341d6747634b8b1fa5461656e5e56076 ↗
- https://git.kernel.org/stable/c/d1a19217995df9c7e4118f5a2820c5032fef2945 ↗
- https://git.kernel.org/stable/c/e3d77f935639e6ae4b381c80464c31df998d61f4 ↗
- https://git.kernel.org/stable/c/db4a9f99b12a7ee1c19d86c83a3b752c7effa6c6 ↗
- https://git.kernel.org/stable/c/6a8d70e2ad6aad2c345a5048edcb8168036f97d6 ↗
- https://git.kernel.org/stable/c/e7fcf179b82d3a3730fd8615da01b087cc654d0b ↗
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html ↗
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html ↗
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html ↗