CVE-2021-47259
NFS: Fix use-after-free in nfs4_init_client()
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Description
In the Linux kernel, the following vulnerability has been resolved: NFS: Fix use-after-free in nfs4_init_client() KASAN reports a use-after-free when attempting to mount two different exports through two different NICs that belong to the same server. Olga was able to hit this with kernels starting somewhere between 5.7 and 5.10, but I traced the patch that introduced the clear_bit() call to 4.13. So something must have changed in the refcounting of the clp pointer to make this call to nfs_put_client() the very last one.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- https://git.kernel.org/stable/c/3e3c7ebbfac152d08be75c92802a64a1f6471a15
- https://git.kernel.org/stable/c/42c10b0db064e45f5c5ae7019bbf2168ffab766c
- https://git.kernel.org/stable/c/476bdb04c501fc64bf3b8464ffddefc8dbe01577
- https://git.kernel.org/stable/c/72651c6579a25317a90536181d311c663d0329ab
- https://git.kernel.org/stable/c/c3b6cf64dfe4ef96e7341508d50d6998da7062c7
References (6)
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