Affected: Linux

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

scsi: ufs: core: Fix device management cmd timeout flow

In the UFS error handling flow, the host will send a device management cmd (NOP OUT) to the device for link recovery. If this cmd times out and clearing the doorbell fails, ufshcd_wait_for_dev_cmd() will do nothing and return. hba->dev_cmd.complete struct is not set to NULL.

When this happens, if cmd has been completed by device, then we will call complete() in __ufshcd_transfer_req_compl(). Because the complete struct is allocated on the stack, the following crash will occur:

ipanic_die+0x24/0x38 [mrdump] die+0x344/0x748 arm64_notify_die+0x44/0x104 do_debug_exception+0x104/0x1e0 el1_dbg+0x38/0x54 el1_sync_handler+0x40/0x88 el1_sync+0x8c/0x140 queued_spin_lock_slowpath+0x2e4/0x3c0 __ufshcd_transfer_req_compl+0x3b0/0x1164 ufshcd_trc_handler+0x15c/0x308 ufshcd_host_reset_and_restore+0x54/0x260 ufshcd_reset_and_restore+0x28c/0x57c ufshcd_err_handler+0xeb8/0x1b6c process_one_work+0x288/0x964 worker_thread+0x4bc/0xc7c kthread+0x15c/0x264 ret_from_fork+0x10/0x30