Zheyu Ma <zheyuma97@xxxxxxxxx> wrote: > When the driver fails to request the firmware, it calls its error > handler. In the error handler, the driver detaches device from driver > first before releasing the firmware, which can cause a use-after-free bug. > > Fix this by releasing firmware first. > > The following log reveals it: > > [ 9.007301 ] BUG: KASAN: use-after-free in mwl8k_fw_state_machine+0x320/0xba0 > [ 9.010143 ] Workqueue: events request_firmware_work_func > [ 9.010830 ] Call Trace: > [ 9.010830 ] dump_stack_lvl+0xa8/0xd1 > [ 9.010830 ] print_address_description+0x87/0x3b0 > [ 9.010830 ] kasan_report+0x172/0x1c0 > [ 9.010830 ] ? mutex_unlock+0xd/0x10 > [ 9.010830 ] ? mwl8k_fw_state_machine+0x320/0xba0 > [ 9.010830 ] ? mwl8k_fw_state_machine+0x320/0xba0 > [ 9.010830 ] __asan_report_load8_noabort+0x14/0x20 > [ 9.010830 ] mwl8k_fw_state_machine+0x320/0xba0 > [ 9.010830 ] ? mwl8k_load_firmware+0x5f0/0x5f0 > [ 9.010830 ] request_firmware_work_func+0x172/0x250 > [ 9.010830 ] ? read_lock_is_recursive+0x20/0x20 > [ 9.010830 ] ? process_one_work+0x7a1/0x1100 > [ 9.010830 ] ? request_firmware_nowait+0x460/0x460 > [ 9.010830 ] ? __this_cpu_preempt_check+0x13/0x20 > [ 9.010830 ] process_one_work+0x9bb/0x1100 > > Signed-off-by: Zheyu Ma <zheyuma97@xxxxxxxxx> Patch applied to wireless-drivers-next.git, thanks. 257051a235c1 mwl8k: Fix use-after-free in mwl8k_fw_state_machine() -- https://patchwork.kernel.org/project/linux-wireless/patch/1634356979-6211-1-git-send-email-zheyuma97@xxxxxxxxx/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
