From: John Garry <john.garry@xxxxxxxxxx> [ Upstream commit c87bf24cfb60bce27b4d2c7e56ebfd86fb9d16bb ] sdebug_max_queue should not exceed SDEBUG_CANQUEUE, otherwise crashes like this can be triggered by passing an out-of-range value: Hardware name: Huawei D06 /D06, BIOS Hisilicon D06 UEFI RC0 - V1.16.01 03/15/2019 pstate: 20400009 (nzCv daif +PAN -UAO BTYPE=--) pc : schedule_resp+0x2a4/0xa70 [scsi_debug] lr : schedule_resp+0x52c/0xa70 [scsi_debug] sp : ffff800022ab36f0 x29: ffff800022ab36f0 x28: ffff0023a935a610 x27: ffff800008e0a648 x26: 0000000000000003 x25: ffff0023e84f3200 x24: 00000000003d0900 x23: 0000000000000000 x22: 0000000000000000 x21: ffff0023be60a320 x20: ffff0023be60b538 x19: ffff800008e13000 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000001 x8 : 0000000000000000 x7 : 0000000000000000 x6 : 00000000000000c1 x5 : 0000020000200000 x4 : dead0000000000ff x3 : 0000000000000200 x2 : 0000000000000200 x1 : ffff800008e13d88 x0 : 0000000000000000 Call trace: schedule_resp+0x2a4/0xa70 [scsi_debug] scsi_debug_queuecommand+0x2c4/0x9e0 [scsi_debug] scsi_queue_rq+0x698/0x840 __blk_mq_try_issue_directly+0x108/0x228 blk_mq_request_issue_directly+0x58/0x98 blk_mq_try_issue_list_directly+0x5c/0xf0 blk_mq_sched_insert_requests+0x18c/0x200 blk_mq_flush_plug_list+0x11c/0x190 blk_flush_plug_list+0xdc/0x110 blk_finish_plug+0x38/0x210 blkdev_direct_IO+0x450/0x4d8 generic_file_read_iter+0x84/0x180 blkdev_read_iter+0x3c/0x50 aio_read+0xc0/0x170 io_submit_one+0x5c8/0xc98 __arm64_sys_io_submit+0x1b0/0x258 el0_svc_common.constprop.3+0x68/0x170 do_el0_svc+0x24/0x90 el0_sync_handler+0x13c/0x1a8 el0_sync+0x158/0x180 Code: 528847e0 72a001e0 6b00003f 540018cd (3941c340) In addition, it should not be less than 1. So add checks for these, and fail the module init for those cases. [mkp: changed if condition to match error message] Link: https://lore.kernel.org/r/1594297400-24756-2-git-send-email-john.garry@xxxxxxxxxx Fixes: c483739430f1 ("scsi_debug: add multiple queue support") Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx> Acked-by: Douglas Gilbert <dgilbert@xxxxxxxxxxxx> Signed-off-by: John Garry <john.garry@xxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/scsi/scsi_debug.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index ac936b5ca74e5..aba1a3396890b 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -4993,6 +4993,12 @@ static int __init scsi_debug_init(void) pr_err("submit_queues must be 1 or more\n"); return -EINVAL; } + + if ((sdebug_max_queue > SDEBUG_CANQUEUE) || (sdebug_max_queue < 1)) { + pr_err("max_queue must be in range [1, %d]\n", SDEBUG_CANQUEUE); + return -EINVAL; + } + sdebug_q_arr = kcalloc(submit_queues, sizeof(struct sdebug_queue), GFP_KERNEL); if (sdebug_q_arr == NULL) -- 2.25.1