[PATCH v2] ufs: core: bsg: Fix memory crash in case arpmb command failed

[Arthur Simchaev]

In case the device doesn't support arpmb, the kernel get memory crash
due to copy user data in bsg_transport_sg_io_fn level. So in case
ufs_bsg_exec_advanced_rpmb_req returned error, do not set the job's
reply_len.

Memory crash backtrace:
3,1290,531166405,-;ufshcd 0000:00:12.5: ARPMB OP failed: error code -22

4,1308,531166555,-;Call Trace:

4,1309,531166559,-; <TASK>

4,1310,531166565,-; ? show_regs+0x6d/0x80

4,1311,531166575,-; ? die+0x37/0xa0

4,1312,531166583,-; ? do_trap+0xd4/0xf0

4,1313,531166593,-; ? do_error_trap+0x71/0xb0

4,1314,531166601,-; ? usercopy_abort+0x6c/0x80

4,1315,531166610,-; ? exc_invalid_op+0x52/0x80

4,1316,531166622,-; ? usercopy_abort+0x6c/0x80

4,1317,531166630,-; ? asm_exc_invalid_op+0x1b/0x20

4,1318,531166643,-; ? usercopy_abort+0x6c/0x80

4,1319,531166652,-; __check_heap_object+0xe3/0x120

4,1320,531166661,-; check_heap_object+0x185/0x1d0

4,1321,531166670,-; __check_object_size.part.0+0x72/0x150

4,1322,531166679,-; __check_object_size+0x23/0x30

4,1323,531166688,-; bsg_transport_sg_io_fn+0x314/0x3b0

Fixes: 6ff265fc5ef6 ("scsi: ufs: core: bsg: Add advanced RPMB support in ufs_bsg")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Arthur Simchaev <arthur.simchaev@xxxxxxxxxxx>

---
Changes in v2:
  - Add Fixes tag
  - Elaborate commit log

Signed-off-by: Arthur Simchaev <arthur.simchaev@xxxxxxxxxxx>
---
 drivers/ufs/core/ufs_bsg.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/ufs/core/ufs_bsg.c b/drivers/ufs/core/ufs_bsg.c
index 8d4ad0a3f2cf..a8ed9bc6e4f1 100644
--- a/drivers/ufs/core/ufs_bsg.c
+++ b/drivers/ufs/core/ufs_bsg.c
@@ -194,10 +194,12 @@ static int ufs_bsg_request(struct bsg_job *job)
 	ufshcd_rpm_put_sync(hba);
 	kfree(buff);
 	bsg_reply->result = ret;
-	job->reply_len = !rpmb ? sizeof(struct ufs_bsg_reply) : sizeof(struct ufs_rpmb_reply);
 	/* complete the job here only if no error */
-	if (ret == 0)
+	if (ret == 0) {
+		job->reply_len = !rpmb ? sizeof(struct ufs_bsg_reply) :
+					 sizeof(struct ufs_rpmb_reply);
 		bsg_job_done(job, ret, bsg_reply->reply_payload_rcv_len);
+	}
 
 	return ret;
 }
-- 
2.34.1