From: Bean Huo beanhuo@micron.com
[ Upstream commit cfcbae3895b86c390ede57b2a8f601dd5972b47b ]
In function __ufshcd_query_descriptor(), in the event of an error happening, we directly goto out_unlock and forget to invaliate hba->dev_cmd.query.descriptor pointer. This results in this pointer still valid in ufshcd_copy_query_response() for other query requests which go through ufshcd_exec_raw_upiu_cmd(). This will cause __memcpy() crash and system hangs. Log as shown below:
Unable to handle kernel paging request at virtual address ffff000012233c40 Mem abort info: ESR = 0x96000047 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000047 CM = 0, WnR = 1 swapper pgtable: 4k pages, 48-bit VAs, pgdp = 0000000028cc735c [ffff000012233c40] pgd=00000000bffff003, pud=00000000bfffe003, pmd=00000000ba8b8003, pte=0000000000000000 Internal error: Oops: 96000047 [#2] PREEMPT SMP ... Call trace: __memcpy+0x74/0x180 ufshcd_issue_devman_upiu_cmd+0x250/0x3c0 ufshcd_exec_raw_upiu_cmd+0xfc/0x1a8 ufs_bsg_request+0x178/0x3b0 bsg_queue_rq+0xc0/0x118 blk_mq_dispatch_rq_list+0xb0/0x538 blk_mq_sched_dispatch_requests+0x18c/0x1d8 __blk_mq_run_hw_queue+0xb4/0x118 blk_mq_run_work_fn+0x28/0x38 process_one_work+0x1ec/0x470 worker_thread+0x48/0x458 kthread+0x130/0x138 ret_from_fork+0x10/0x1c Code: 540000ab a8c12027 a88120c7 a8c12027 (a88120c7) ---[ end trace 793e1eb5dff69f2d ]--- note: kworker/0:2H[2054] exited with preempt_count 1
This patch is to move "descriptor = NULL" down to below the label "out_unlock".
Fixes: d44a5f98bb49b2(ufs: query descriptor API) Link: https://lore.kernel.org/r/20191112223436.27449-3-huobean@gmail.com Reviewed-by: Alim Akhtar alim.akhtar@samsung.com Reviewed-by: Bart Van Assche bvanassche@acm.org Signed-off-by: Bean Huo beanhuo@micron.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/ufs/ufshcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 11a87f51c442..358ff7b01568 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -2986,10 +2986,10 @@ static int __ufshcd_query_descriptor(struct ufs_hba *hba, goto out_unlock; }
- hba->dev_cmd.query.descriptor = NULL; *buf_len = be16_to_cpu(response->upiu_res.length);
out_unlock: + hba->dev_cmd.query.descriptor = NULL; mutex_unlock(&hba->dev_cmd.lock); out: ufshcd_release(hba);