CVE-2021-47259
Published: May 21, 2024
Modified: May 11, 2026
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.
| Vendor | Product | Versions |
|---|---|---|
Linux | Linux | affected 8dcbec6d20eb881ba368d0aebc3a8a678aebb1da - < c7eab9e2d7b4e983ce280276fb920af649955897affected 8dcbec6d20eb881ba368d0aebc3a8a678aebb1da - < 42c10b0db064e45f5c5ae7019bbf2168ffab766caffected 8dcbec6d20eb881ba368d0aebc3a8a678aebb1da - < 3e3c7ebbfac152d08be75c92802a64a1f6471a15affected 8dcbec6d20eb881ba368d0aebc3a8a678aebb1da - < c3b6cf64dfe4ef96e7341508d50d6998da7062c7affected 8dcbec6d20eb881ba368d0aebc3a8a678aebb1da - < 72651c6579a25317a90536181d311c663d0329ab+1 more versions |
Linux | Linux | affected 4.13unaffected 0 - < 4.13unaffected 4.14.237 - <= 4.14.*unaffected 4.19.195 - <= 4.19.*unaffected 5.4.126 - <= 5.4.*+3 more versions |
References
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