KMSAN found the following issue:
BUG: KMSAN: uninit-value in sr_check_events+0x365/0x1460
sr_check_events+0x365/0x1460
cdrom_check_events+0x66/0x170
sr_block_check_events+0xf2/0x130
disk_check_events+0xec/0x900
bdev_check_media_change+0x2a6/0x7d0
sr_block_open+0x154/0x320
blkdev_get_whole+0xa8/0x6c0
blkdev_get_by_dev+0x50f/0x1200
blkdev_open+0x215/0x430
do_dentry_open+0xfbd/0x19a0
vfs_open+0x7b/0xa0
path_openat+0x4a54/0x5b40
do_filp_open+0x24d/0x660
do_sys_openat2+0x1f0/0x910
__x64_sys_openat+0x2b4/0x330
do_syscall_64+0x41/0xc0
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Local variable sshdr.i created at:
sr_check_events+0x131/0x1460
cdrom_check_events+0x66/0x170
sr_get_events() can access uninitialized local variable sshdr when
scsi_execute_cmd() returns error. This patch fixes the issue by
checking the result before accessing sshdr.
Fixes: 93aae17af117 ("sr: implement sr_check_events()")
Signed-off-by: Shigeru Yoshida <syoshida@xxxxxxxxxx>
---
drivers/scsi/sr.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 12869e6d4ebd..86b43c069a44 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -177,10 +177,13 @@ static unsigned int sr_get_events(struct scsi_device *sdev)
result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, buf, sizeof(buf),
SR_TIMEOUT, MAX_RETRIES, &exec_args);
+ if (result)
+ return 0;
+
if (scsi_sense_valid(&sshdr) && sshdr.sense_key == UNIT_ATTENTION)
return DISK_EVENT_MEDIA_CHANGE;
- if (result || be16_to_cpu(eh->data_len) < sizeof(*med))
+ if (be16_to_cpu(eh->data_len) < sizeof(*med))
return 0;
if (eh->nea || eh->notification_class != 0x4)
--
2.39.0
