Detections
Analytics
CVE-2021-47388
medium
Description
In the Linux kernel, the following vulnerability has been resolved: mac80211: fix use-after-free in CCMP/GCMP RX When PN checking is done in mac80211, for fragmentation we need to copy the PN to the RX struct so we can later use it to do a comparison, since commit bf30ca922a0c ("mac80211: check defrag PN against current frame"). Unfortunately, in that commit I used the 'hdr' variable without it being necessarily valid, so use-after-free could occur if it was necessary to reallocate (parts of) the frame. Fix this by reloading the variable after the code that results in the reallocations, if any. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=214401.
References
https://git.kernel.org/stable/c/f556e1d6fb9f2923a9a36f3df638c7d79ba09dbb
https://git.kernel.org/stable/c/94513069eb549737bcfc3d988d6ed4da948a2de8
https://git.kernel.org/stable/c/57de2dcb18742dc2860861c9f496da7d42b67da0
https://git.kernel.org/stable/c/50149e0866a82cef33e680ee68dc380a5bc75d32
https://git.kernel.org/stable/c/447d001b875d0e7f211c4ba004916028da994258
https://git.kernel.org/stable/c/3d5d629c99c468458022e9b381789de3595bf4dd
https://git.kernel.org/stable/c/31de381aef0ab1b342f62485118dc8a19363dc78
https://git.kernel.org/stable/c/27d3eb5616ee2c0a3b30c3fa34813368ed1f3dc9