In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrumacltcam: Fix NULL pointer dereference in error path
When calling mlxswspacltcamregion_destroy() from an error path after failing to attach the region to an ACL group, we hit a NULL pointer dereference upon 'region->group->tcam' [1].
Fix by retrieving the 'tcam' pointer using mlxswspacltotcam().
[1] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] RIP: 0010:mlxswspacltcamregiondestroy+0xa0/0xd0 [...] Call Trace: mlxswspacltcamvchunkget+0x88b/0xa20 mlxswspacltcamventryadd+0x25/0xe0 mlxswspaclruleadd+0x47/0x240 mlxswspflowerreplace+0x1a9/0x1d0 tcsetupcbadd+0xdc/0x1c0 flhwreplacefilter+0x146/0x1f0 flchange+0xc17/0x1360 tcnewtfilter+0x472/0xb90 rtnetlinkrcvmsg+0x313/0x3b0 netlinkrcvskb+0x58/0x100 netlinkunicast+0x244/0x390 netlinksendmsg+0x1e4/0x440 syssendmsg+0x164/0x260 syssendmsg+0x9a/0xe0 _syssendmsg+0x7a/0xc0 dosyscall64+0x40/0xe0 entrySYSCALL64afterhwframe+0x63/0x6b