Hi,
We would like to report the following bug which has been found by our
modified version of syzkaller.
======================================================
description: KMSAN: uninit-value in sr_check_events
affected file: drivers/scsi/sr.c
kernel version: 6.2.0-rc5
kernel commit: 41c66f47061608dc1fd493eebce198f0e74cc2d7
git tree: kmsan
kernel config: https://syzkaller.appspot.com/text?tag=KernelConfig&x=a9a22da1efde3af6
crash reproducer: attached
======================================================
Crash log:
======================================================
BUG: KMSAN: uninit-value in sr_check_events+0x12d2/0x13c0 drivers/scsi/sr.c:269
sr_check_events+0x12d2/0x13c0 drivers/scsi/sr.c:269
cdrom_update_events drivers/cdrom/cdrom.c:1485 [inline]
cdrom_check_events+0x61/0x170 drivers/cdrom/cdrom.c:1495
sr_block_check_events+0xf5/0x130 drivers/scsi/sr.c:559
disk_check_events+0xf1/0x950 block/disk-events.c:193
disk_clear_events block/disk-events.c:248 [inline]
bdev_check_media_change+0x26a/0x7f0 block/disk-events.c:279
sr_block_open+0x159/0x340 drivers/scsi/sr.c:494
blkdev_get_whole+0xb4/0x700 block/bdev.c:672
blkdev_get_by_dev+0x4c9/0x1280 block/bdev.c:822
blkdev_open+0x216/0x440 block/fops.c:478
do_dentry_open+0xf85/0x1970 fs/open.c:882
vfs_open+0x75/0xa0 fs/open.c:1013
do_open fs/namei.c:3557 [inline]
path_openat+0x4c4b/0x5a00 fs/namei.c:3714
do_filp_open+0x252/0x660 fs/namei.c:3741
do_sys_openat2+0x200/0x920 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_openat fs/open.c:1342 [inline]
__se_sys_openat fs/open.c:1337 [inline]
__x64_sys_openat+0x285/0x310 fs/open.c:1337
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Uninit was stored to memory at:
sr_check_events+0xb04/0x13c0 drivers/scsi/sr.c:216
cdrom_update_events drivers/cdrom/cdrom.c:1485 [inline]
cdrom_check_events+0x61/0x170 drivers/cdrom/cdrom.c:1495
sr_block_check_events+0xf5/0x130 drivers/scsi/sr.c:559
disk_check_events+0xf1/0x950 block/disk-events.c:193
disk_clear_events block/disk-events.c:248 [inline]
bdev_check_media_change+0x26a/0x7f0 block/disk-events.c:279
sr_block_open+0x159/0x340 drivers/scsi/sr.c:494
blkdev_get_whole+0xb4/0x700 block/bdev.c:672
blkdev_get_by_dev+0x4c9/0x1280 block/bdev.c:822
blkdev_open+0x216/0x440 block/fops.c:478
do_dentry_open+0xf85/0x1970 fs/open.c:882
vfs_open+0x75/0xa0 fs/open.c:1013
do_open fs/namei.c:3557 [inline]
path_openat+0x4c4b/0x5a00 fs/namei.c:3714
do_filp_open+0x252/0x660 fs/namei.c:3741
do_sys_openat2+0x200/0x920 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_openat fs/open.c:1342 [inline]
__se_sys_openat fs/open.c:1337 [inline]
__x64_sys_openat+0x285/0x310 fs/open.c:1337
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Local variable sshdr.i created at:
sr_get_events drivers/scsi/sr.c:172 [inline]
sr_check_events+0x11f/0x13c0 drivers/scsi/sr.c:215
cdrom_update_events drivers/cdrom/cdrom.c:1485 [inline]
cdrom_check_events+0x61/0x170 drivers/cdrom/cdrom.c:1495
CPU: 0 PID: 22994 Comm: syz-executor.1 Not tainted
6.2.0-rc5-00010-g41c66f470616 #8
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
--
Thanks and Regards,
Dipanjan