Affected: Linux

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

wifi: mt76: mt7925: prevent NULL pointer dereference in mt7925_sta_set_decap_offload()

Add a NULL check for msta->vif before accessing its members to prevent a kernel panic in AP mode deployment. This also fix the issue reported in [1].

The crash occurs when this function is triggered before the station is fully initialized. The call trace shows a page fault at mt7925_sta_set_decap_offload() due to accessing resources when msta->vif is NULL.

Fix this by adding an early return if msta->vif is NULL and also check wcid.sta is ready. This ensures we only proceed with decap offload configuration when the station's state is properly initialized.

[14739.655703] Unable to handle kernel paging request at virtual address ffffffffffffffa0 [14739.811820] CPU: 0 UID: 0 PID: 895854 Comm: hostapd Tainted: G [14739.821394] Tainted: [C]=CRAP, [O]=OOT_MODULE [14739.825746] Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT) [14739.831577] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [14739.838538] pc : mt7925_sta_set_decap_offload+0xc0/0x1b8 [mt7925_common] [14739.845271] lr : mt7925_sta_set_decap_offload+0x58/0x1b8 [mt7925_common] [14739.851985] sp : ffffffc085efb500 [14739.855295] x29: ffffffc085efb500 x28: 0000000000000000 x27: ffffff807803a158 [14739.862436] x26: ffffff8041ececb8 x25: 0000000000000001 x24: 0000000000000001 [14739.869577] x23: 0000000000000001 x22: 0000000000000008 x21: ffffff8041ece…