syzbot


KMSAN: kernel-infoleak in scsi_cmd_ioctl

Status: fixed on 2020/11/16 12:12
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+85433a479a646a064ab3@syzkaller.appspotmail.com
Fix commit: 6d53a9fe5a19 block/scsi-ioctl: Fix kernel-infoleak in scsi_put_cdrom_generic_arg()
First crash: 1339d, last: 1262d
Discussions (4)
Title Replies (including bot) Last reply
[PATCH 5.8 000/124] 5.8.15-rc1 review 136 (136) 2020/10/14 18:31
[PATCH v4] block/scsi-ioctl: Fix kernel-infoleak in scsi_put_cdrom_generic_arg() 2 (2) 2020/10/02 18:02
KMSAN: kernel-infoleak in scsi_cmd_ioctl 2 (3) 2020/10/02 14:00
Re: KMSAN: kernel-infoleak in scsi_cmd_ioctl 1 (1) 2020/09/30 15:53

Sample crash report:
=====================================================
BUG: KMSAN: kernel-infoleak in kmsan_copy_to_user+0x9c/0xb0 mm/kmsan/kmsan_hooks.c:253
CPU: 0 PID: 15632 Comm: syz-executor.5 Not tainted 5.9.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122
 kmsan_internal_check_memory+0x202/0x520 mm/kmsan/kmsan.c:410
 kmsan_copy_to_user+0x9c/0xb0 mm/kmsan/kmsan_hooks.c:253
 instrument_copy_to_user include/linux/instrumented.h:91 [inline]
 _copy_to_user+0x18e/0x260 lib/usercopy.c:30
 scsi_put_cdrom_generic_arg include/linux/uaccess.h:177 [inline]
 scsi_cdrom_send_packet block/scsi_ioctl.c:770 [inline]
 scsi_cmd_ioctl+0x241f/0x2590 block/scsi_ioctl.c:827
 scsi_cmd_blk_ioctl+0x1f6/0x240 block/scsi_ioctl.c:876
 sd_ioctl_common+0x50a/0x5c0 drivers/scsi/sd.c:1531
 sd_compat_ioctl+0xc5/0x220 drivers/scsi/sd.c:1733
 compat_blkdev_ioctl+0x705/0x11a0 block/ioctl.c:691
 __do_compat_sys_ioctl fs/ioctl.c:842 [inline]
 __se_compat_sys_ioctl+0x53d/0x1100 fs/ioctl.c:793
 __ia32_compat_sys_ioctl+0x4a/0x70 fs/ioctl.c:793
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f52549
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f554c0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000005393
RDX: 0000000020006400 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Local variable ----cgc32.i42.i@scsi_cmd_ioctl created at:
 scsi_put_cdrom_generic_arg block/scsi_ioctl.c:695 [inline]
 scsi_cdrom_send_packet block/scsi_ioctl.c:770 [inline]
 scsi_cmd_ioctl+0x2254/0x2590 block/scsi_ioctl.c:827
 scsi_put_cdrom_generic_arg block/scsi_ioctl.c:695 [inline]
 scsi_cdrom_send_packet block/scsi_ioctl.c:770 [inline]
 scsi_cmd_ioctl+0x2254/0x2590 block/scsi_ioctl.c:827

Bytes 29-31 of 44 are uninitialized
Memory access of size 44 starts at ffff8880291e7ad0
Data copied to user address 0000000020006400
=====================================================

Crashes (131):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/11/12 08:59 https://github.com/google/kmsan.git master e16174226146 cca87986 .config console log report info ci-upstream-kmsan-gce-386
2020/11/11 09:02 https://github.com/google/kmsan.git master e16174226146 cca87986 .config console log report info ci-upstream-kmsan-gce-386
2020/11/11 07:50 https://github.com/google/kmsan.git master e16174226146 cca87986 .config console log report info ci-upstream-kmsan-gce-386
2020/11/09 21:03 https://github.com/google/kmsan.git master e16174226146 64069d48 .config console log report info ci-upstream-kmsan-gce-386
2020/11/09 10:24 https://github.com/google/kmsan.git master e16174226146 64069d48 .config console log report info ci-upstream-kmsan-gce-386
2020/11/08 00:36 https://github.com/google/kmsan.git master e16174226146 64069d48 .config console log report info ci-upstream-kmsan-gce-386
2020/11/04 16:30 https://github.com/google/kmsan.git master e16174226146 cba33199 .config console log report info ci-upstream-kmsan-gce-386
2020/11/04 09:17 https://github.com/google/kmsan.git master e16174226146 cba33199 .config console log report info ci-upstream-kmsan-gce-386
2020/11/04 03:42 https://github.com/google/kmsan.git master e16174226146 cba33199 .config console log report info ci-upstream-kmsan-gce-386
2020/11/01 20:28 https://github.com/google/kmsan.git master e16174226146 8bc4594f .config console log report info ci-upstream-kmsan-gce-386
2020/11/01 09:49 https://github.com/google/kmsan.git master e16174226146 8bc4594f .config console log report info ci-upstream-kmsan-gce-386
2020/11/01 06:11 https://github.com/google/kmsan.git master e16174226146 8bc4594f .config console log report info ci-upstream-kmsan-gce-386
2020/10/29 10:32 https://github.com/google/kmsan.git master e16174226146 f24824d3 .config console log report info ci-upstream-kmsan-gce-386
2020/10/29 07:22 https://github.com/google/kmsan.git master e16174226146 f24824d3 .config console log report info ci-upstream-kmsan-gce-386
2020/10/29 00:35 https://github.com/google/kmsan.git master e16174226146 f24824d3 .config console log report info ci-upstream-kmsan-gce-386
2020/10/25 01:22 https://github.com/google/kmsan.git master e16174226146 a1839e81 .config console log report info ci-upstream-kmsan-gce-386
2020/10/24 10:57 https://github.com/google/kmsan.git master e16174226146 2bb6666c .config console log report info ci-upstream-kmsan-gce-386
2020/10/22 17:47 https://github.com/google/kmsan.git master e16174226146 be6b1582 .config console log report info ci-upstream-kmsan-gce-386
2020/10/19 08:35 https://github.com/google/kmsan.git master e67f4ba870c2 fea47c01 .config console log report info ci-upstream-kmsan-gce-386
2020/10/18 18:45 https://github.com/google/kmsan.git master e67f4ba870c2 fea47c01 .config console log report info ci-upstream-kmsan-gce-386
2020/10/18 13:11 https://github.com/google/kmsan.git master e67f4ba870c2 fea47c01 .config console log report info ci-upstream-kmsan-gce-386
2020/10/18 10:29 https://github.com/google/kmsan.git master e67f4ba870c2 fea47c01 .config console log report info ci-upstream-kmsan-gce-386
2020/10/17 08:02 https://github.com/google/kmsan.git master e67f4ba870c2 6e262c73 .config console log report info ci-upstream-kmsan-gce-386
2020/10/16 04:36 https://github.com/google/kmsan.git master e67f4ba870c2 6e262c73 .config console log report info ci-upstream-kmsan-gce-386
2020/10/11 14:21 https://github.com/google/kmsan.git master e67f4ba870c2 4a77ae0b .config console log report info ci-upstream-kmsan-gce-386
2020/10/11 12:58 https://github.com/google/kmsan.git master e67f4ba870c2 4a77ae0b .config console log report info ci-upstream-kmsan-gce-386
2020/10/09 11:05 https://github.com/google/kmsan.git master 5edb1df295b9 92390980 .config console log report info ci-upstream-kmsan-gce-386
2020/10/09 06:43 https://github.com/google/kmsan.git master 5edb1df295b9 92390980 .config console log report info ci-upstream-kmsan-gce-386
2020/10/08 00:34 https://github.com/google/kmsan.git master 5edb1df295b9 1880b4a9 .config console log report info ci-upstream-kmsan-gce-386
2020/10/07 01:11 https://github.com/google/kmsan.git master 5edb1df295b9 1880b4a9 .config console log report info ci-upstream-kmsan-gce-386
2020/10/05 00:04 https://github.com/google/kmsan.git master 5edb1df295b9 5ef9c291 .config console log report info ci-upstream-kmsan-gce-386
2020/10/03 18:53 https://github.com/google/kmsan.git master 5edb1df295b9 2653fa43 .config console log report info ci-upstream-kmsan-gce-386
2020/10/03 12:59 https://github.com/google/kmsan.git master 5edb1df295b9 2653fa43 .config console log report info ci-upstream-kmsan-gce-386
2020/10/03 01:22 https://github.com/google/kmsan.git master 5edb1df295b9 4969d6ca .config console log report info ci-upstream-kmsan-gce-386
2020/10/02 09:17 https://github.com/google/kmsan.git master 5edb1df295b9 9602ddf4 .config console log report info ci-upstream-kmsan-gce-386
2020/10/02 07:52 https://github.com/google/kmsan.git master 5edb1df295b9 9602ddf4 .config console log report info ci-upstream-kmsan-gce-386
2020/10/02 04:32 https://github.com/google/kmsan.git master 5edb1df295b9 9602ddf4 .config console log report info ci-upstream-kmsan-gce-386
2020/10/01 19:09 https://github.com/google/kmsan.git master 5edb1df295b9 a9767fb2 .config console log report info ci-upstream-kmsan-gce-386
2020/09/30 10:49 https://github.com/google/kmsan.git master 5edb1df295b9 5abc3f1a .config console log report info ci-upstream-kmsan-gce-386
2020/09/30 05:35 https://github.com/google/kmsan.git master 5edb1df295b9 5abc3f1a .config console log report info ci-upstream-kmsan-gce-386
2020/09/29 13:13 https://github.com/google/kmsan.git master 5edb1df295b9 1b88c6d5 .config console log report info ci-upstream-kmsan-gce-386
2020/08/30 10:17 https://github.com/google/kmsan.git master 3b3ea6028136 d5a3ae1f .config console log report ci-upstream-kmsan-gce-386
2020/08/27 10:05 https://github.com/google/kmsan.git master ce8056d1f79e 816e0689 .config console log report ci-upstream-kmsan-gce-386
2020/08/27 09:59 https://github.com/google/kmsan.git master ce8056d1f79e 816e0689 .config console log report ci-upstream-kmsan-gce-386
* Struck through repros no longer work on HEAD.