Description
In the Linux kernel, the following vulnerability has been resolved: atm: clip: Fix potential null-ptr-deref in to_atmarpd(). atmarpd is protected by RTNL since commit f3a0592b37b8 ("[ATM]: clip causes unregister hang"). However, it is not enough because to_atmarpd() is called without RTNL, especially clip_neigh_solicit() / neigh_ops->solicit() is unsleepable. Also, there is no RTNL dependency around atmarpd. Let's use a private mutex and RCU to protect access to atmarpd in to_atmarpd().
Product status
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before a4c5785feb979cd996a99cfaad8bf353b2e79301
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 70eac9ba7ce25d99c1d99bbf4ddb058940f631f9
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 3251ce3979f41bd228f77a7615f9dd616d06a110
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before ee4d9e4ddf3f9c4ee2ec0a3aad6196ee36d30e57
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 06935c50cfa3ac57cce80bba67b6d38ec1406e92
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 36caab990b69ef4eec1d81c52a19f080b7daa059
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before f58e4270c73e7f086322978d585ea67c8076ce49
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 706cc36477139c1616a9b2b96610a8bb520b7119
2.6.12
Any version before 2.6.12
5.4.296 (semver)
5.10.240 (semver)
5.15.189 (semver)
6.1.146 (semver)
6.6.99 (semver)
6.12.39 (semver)
6.15.7 (semver)
6.16 (original_commit_for_fix)
References
lists.debian.org/debian-lts-announce/2025/10/msg00008.html
lists.debian.org/debian-lts-announce/2025/10/msg00007.html
git.kernel.org/...c/a4c5785feb979cd996a99cfaad8bf353b2e79301
git.kernel.org/...c/70eac9ba7ce25d99c1d99bbf4ddb058940f631f9
git.kernel.org/...c/3251ce3979f41bd228f77a7615f9dd616d06a110
git.kernel.org/...c/ee4d9e4ddf3f9c4ee2ec0a3aad6196ee36d30e57
git.kernel.org/...c/06935c50cfa3ac57cce80bba67b6d38ec1406e92
git.kernel.org/...c/36caab990b69ef4eec1d81c52a19f080b7daa059
git.kernel.org/...c/f58e4270c73e7f086322978d585ea67c8076ce49
git.kernel.org/...c/706cc36477139c1616a9b2b96610a8bb520b7119