Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

wifi: mac80211: abort chanswitch when leaving a mesh

The code in ieee80211_stop_mesh() leaves CSA active, but leaving the mesh released the channel context, so the CSA finalize work crashes:

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003 KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] RIP: 0010:ieee80211_put_srates_elem+0x42/0x640 net/mac80211/util.c:3272 Call Trace: ieee80211_mesh_build_beacon+0xa83/0x1b50 net/mac80211/mesh.c:1093 ieee80211_mesh_rebuild_beacon+0xc7/0x170 net/mac80211/mesh.c:1147 ieee80211_mesh_finish_csa+0x131/0x210 net/mac80211/mesh.c:1542 ieee80211_set_after_csa_beacon net/mac80211/cfg.c:4085 [inline] __ieee80211_csa_finalize net/mac80211/cfg.c:4133 [inline] ieee80211_csa_finalize+0x633/0x1150 net/mac80211/cfg.c:4155 cfg80211_wiphy_work+0x2ab/0x450 net/wireless/core.c:438

Abort the channel switch properly.