2019-07-30 12:29:58

by syzbot

[permalink] [raw]
Subject: KASAN: slab-out-of-bounds Read in hidraw_ioctl

Hello,

syzbot found the following crash on:

HEAD commit: 7f7867ff usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=15e293c8600000
kernel config: https://syzkaller.appspot.com/x/.config?x=792eb47789f57810
dashboard link: https://syzkaller.appspot.com/bug?extid=5a6c4ec678a0c6ee84ba
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: [email protected]

==================================================================
BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
Read of size 1 at addr ffff8881ca981f10 by task syz-executor.4/7644

CPU: 1 PID: 7644 Comm: syz-executor.4 Not tainted 5.3.0-rc2+ #23
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+0xca/0x13e lib/dump_stack.c:113
print_address_description+0x6a/0x32c mm/kasan/report.c:351
__kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
kasan_report+0xe/0x12 mm/kasan/common.c:612
strlen+0x79/0x90 lib/string.c:525
strlen include/linux/string.h:281 [inline]
hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fed5bb22c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
RDX: 0000000020000180 RSI: 0000000080404805 RDI: 0000000000000003
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fed5bb236d4
R13: 00000000004c21c6 R14: 00000000004d5528 R15: 00000000ffffffff

Allocated by task 1607:
save_stack+0x1b/0x80 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_kmalloc mm/kasan/common.c:487 [inline]
__kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:460
kmalloc include/linux/slab.h:552 [inline]
syslog_print kernel/printk/printk.c:1346 [inline]
do_syslog kernel/printk/printk.c:1519 [inline]
do_syslog+0x540/0x1380 kernel/printk/printk.c:1493
kmsg_read+0x8a/0xb0 fs/proc/kmsg.c:40
proc_reg_read+0x1c1/0x280 fs/proc/inode.c:223
__vfs_read+0x76/0x100 fs/read_write.c:425
vfs_read+0x1ea/0x430 fs/read_write.c:461
ksys_read+0x127/0x250 fs/read_write.c:587
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 1607:
save_stack+0x1b/0x80 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_slab_free+0x130/0x180 mm/kasan/common.c:449
slab_free_hook mm/slub.c:1423 [inline]
slab_free_freelist_hook mm/slub.c:1470 [inline]
slab_free mm/slub.c:3012 [inline]
kfree+0xe4/0x2f0 mm/slub.c:3953
syslog_print kernel/printk/printk.c:1405 [inline]
do_syslog kernel/printk/printk.c:1519 [inline]
do_syslog+0x1098/0x1380 kernel/printk/printk.c:1493
kmsg_read+0x8a/0xb0 fs/proc/kmsg.c:40
proc_reg_read+0x1c1/0x280 fs/proc/inode.c:223
__vfs_read+0x76/0x100 fs/read_write.c:425
vfs_read+0x1ea/0x430 fs/read_write.c:461
ksys_read+0x127/0x250 fs/read_write.c:587
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881ca981b00
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 16 bytes to the right of
1024-byte region [ffff8881ca981b00, ffff8881ca981f00)
The buggy address belongs to the page:
page:ffffea00072a6000 refcount:1 mapcount:0 mapping:ffff8881da002280
index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da002280
raw: 0000000000000000 00000000000e000e 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff8881ca981e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8881ca981e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8881ca981f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8881ca981f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8881ca982000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at [email protected].

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.


2019-08-11 20:47:54

by syzbot

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

syzbot has found a reproducer for the following crash on:

HEAD commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=150426ba600000
kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
dashboard link: https://syzkaller.appspot.com/bug?extid=5a6c4ec678a0c6ee84ba
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12725c02600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=162163c2600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: [email protected]

==================================================================
BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
Read of size 1 at addr ffff8881d29bdf38 by task syz-executor201/1726

CPU: 1 PID: 1726 Comm: syz-executor201 Not tainted 5.3.0-rc2+ #25
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+0xca/0x13e lib/dump_stack.c:113
print_address_description+0x6a/0x32c mm/kasan/report.c:351
__kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
kasan_report+0xe/0x12 mm/kasan/common.c:612
strlen+0x79/0x90 lib/string.c:525
strlen include/linux/string.h:281 [inline]
hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x445679
Code: e8 5c ad 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 9b cd fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc8514f3a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445679
RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
RBP: 00000000006d0018 R08: 000000000000000b R09: 00000000004002e0
R10: 000000000000000f R11: 0000000000000246 R12: 00000000004028a0
R13: 0000000000402930 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 0:
(stack is not available)

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8881d29bde60
which belongs to the cache shmem_inode_cache of size 1168
The buggy address is located 216 bytes inside of
1168-byte region [ffff8881d29bde60, ffff8881d29be2f0)
The buggy address belongs to the page:
page:ffffea00074a6f00 refcount:1 mapcount:0 mapping:ffff8881da115180
index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da115180
raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff8881d29bde00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8881d29bde80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881d29bdf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8881d29bdf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8881d29be000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

2019-08-21 13:00:42

by Andrey Konovalov

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

On Wed, Aug 21, 2019 at 2:57 PM Andrey Konovalov <[email protected]> wrote:
>
> On Sun, Aug 11, 2019 at 10:46 PM syzbot
> <[email protected]> wrote:
> >
> > syzbot has found a reproducer for the following crash on:
> >
> > HEAD commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
> > git tree: https://github.com/google/kasan.git usb-fuzzer
> > console output: https://syzkaller.appspot.com/x/log.txt?x=150426ba600000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> > dashboard link: https://syzkaller.appspot.com/bug?extid=5a6c4ec678a0c6ee84ba
> > compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12725c02600000
> > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=162163c2600000
> >
> > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > Reported-by: [email protected]
> >
> > ==================================================================
> > BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
> > Read of size 1 at addr ffff8881d29bdf38 by task syz-executor201/1726
> >
> > CPU: 1 PID: 1726 Comm: syz-executor201 Not tainted 5.3.0-rc2+ #25
> > 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+0xca/0x13e lib/dump_stack.c:113
> > print_address_description+0x6a/0x32c mm/kasan/report.c:351
> > __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
> > kasan_report+0xe/0x12 mm/kasan/common.c:612
> > strlen+0x79/0x90 lib/string.c:525
> > strlen include/linux/string.h:281 [inline]
> > hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
> > vfs_ioctl fs/ioctl.c:46 [inline]
> > file_ioctl fs/ioctl.c:509 [inline]
> > do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
> > ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
> > __do_sys_ioctl fs/ioctl.c:720 [inline]
> > __se_sys_ioctl fs/ioctl.c:718 [inline]
> > __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
> > do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
> > entry_SYSCALL_64_after_hwframe+0x49/0xbe
> > RIP: 0033:0x445679
> > Code: e8 5c ad 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7
> > 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
> > ff 0f 83 9b cd fb ff c3 66 2e 0f 1f 84 00 00 00 00
> > RSP: 002b:00007ffc8514f3a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> > RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445679
> > RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
> > RBP: 00000000006d0018 R08: 000000000000000b R09: 00000000004002e0
> > R10: 000000000000000f R11: 0000000000000246 R12: 00000000004028a0
> > R13: 0000000000402930 R14: 0000000000000000 R15: 0000000000000000
> >
> > Allocated by task 0:
> > (stack is not available)
> >
> > Freed by task 0:
> > (stack is not available)
> >
> > The buggy address belongs to the object at ffff8881d29bde60
> > which belongs to the cache shmem_inode_cache of size 1168
> > The buggy address is located 216 bytes inside of
> > 1168-byte region [ffff8881d29bde60, ffff8881d29be2f0)
> > The buggy address belongs to the page:
> > page:ffffea00074a6f00 refcount:1 mapcount:0 mapping:ffff8881da115180
> > index:0x0 compound_mapcount: 0
> > flags: 0x200000000010200(slab|head)
> > raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da115180
> > raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
> > page dumped because: kasan: bad access detected
> >
> > Memory state around the buggy address:
> > ffff8881d29bde00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > ffff8881d29bde80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > > ffff8881d29bdf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > ^
> > ffff8881d29bdf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > ffff8881d29be000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > ==================================================================
> >
>
> Trying Alan's fix from another thread here:
>
> #syz test: https://github.com/google/kasan.git usb-fuzzer e96407b4

><

#syz test: https://github.com/google/kasan.git e96407b4

Attachments:
logitech.patch (1.17 kB)

2019-08-21 13:38:25

by syzbot

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

Hello,

syzbot has tested the proposed patch but the reproducer still triggered
crash:
KASAN: slab-out-of-bounds Read in hidraw_ioctl

==================================================================
BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
Read of size 1 at addr ffff8881c8035f38 by task syz-executor.4/2833

CPU: 1 PID: 2833 Comm: syz-executor.4 Not tainted 5.3.0-rc2+ #1
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+0xca/0x13e lib/dump_stack.c:113
print_address_description+0x6a/0x32c mm/kasan/report.c:351
__kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
kasan_report+0xe/0x12 mm/kasan/common.c:612
strlen+0x79/0x90 lib/string.c:525
strlen include/linux/string.h:281 [inline]
hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f7a68f6dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7a68f6e6d4
R13: 00000000004c21de R14: 00000000004d5620 R15: 00000000ffffffff

Allocated by task 0:
(stack is not available)

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8881c8035e60
which belongs to the cache shmem_inode_cache of size 1168
The buggy address is located 216 bytes inside of
1168-byte region [ffff8881c8035e60, ffff8881c80362f0)
The buggy address belongs to the page:
page:ffffea0007200d00 refcount:1 mapcount:0 mapping:ffff8881da115180
index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da115180
raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff8881c8035e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8881c8035e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881c8035f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8881c8035f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8881c8036000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================


Tested on:

commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git
console output: https://syzkaller.appspot.com/x/log.txt?x=14f14a1e600000
kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
patch: https://syzkaller.appspot.com/x/patch.diff?x=171cd95a600000

2019-08-21 14:12:26

by Andrey Konovalov

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

On Wed, Aug 21, 2019 at 3:37 PM syzbot
<[email protected]> wrote:
>
> Hello,
>
> syzbot has tested the proposed patch but the reproducer still triggered
> crash:
> KASAN: slab-out-of-bounds Read in hidraw_ioctl

Same here, a different bug.

>
> ==================================================================
> BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
> Read of size 1 at addr ffff8881c8035f38 by task syz-executor.4/2833
>
> CPU: 1 PID: 2833 Comm: syz-executor.4 Not tainted 5.3.0-rc2+ #1
> 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+0xca/0x13e lib/dump_stack.c:113
> print_address_description+0x6a/0x32c mm/kasan/report.c:351
> __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
> kasan_report+0xe/0x12 mm/kasan/common.c:612
> strlen+0x79/0x90 lib/string.c:525
> strlen include/linux/string.h:281 [inline]
> hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
> vfs_ioctl fs/ioctl.c:46 [inline]
> file_ioctl fs/ioctl.c:509 [inline]
> do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
> ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
> __do_sys_ioctl fs/ioctl.c:720 [inline]
> __se_sys_ioctl fs/ioctl.c:718 [inline]
> __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
> do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x459829
> Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
> 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
> ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007f7a68f6dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
> RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
> RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7a68f6e6d4
> R13: 00000000004c21de R14: 00000000004d5620 R15: 00000000ffffffff
>
> Allocated by task 0:
> (stack is not available)
>
> Freed by task 0:
> (stack is not available)
>
> The buggy address belongs to the object at ffff8881c8035e60
> which belongs to the cache shmem_inode_cache of size 1168
> The buggy address is located 216 bytes inside of
> 1168-byte region [ffff8881c8035e60, ffff8881c80362f0)
> The buggy address belongs to the page:
> page:ffffea0007200d00 refcount:1 mapcount:0 mapping:ffff8881da115180
> index:0x0 compound_mapcount: 0
> flags: 0x200000000010200(slab|head)
> raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da115180
> raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
> page dumped because: kasan: bad access detected
>
> Memory state around the buggy address:
> ffff8881c8035e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881c8035e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > ffff8881c8035f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ^
> ffff8881c8035f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881c8036000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ==================================================================
>
>
> Tested on:
>
> commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
> git tree: https://github.com/google/kasan.git
> console output: https://syzkaller.appspot.com/x/log.txt?x=14f14a1e600000
> kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> patch: https://syzkaller.appspot.com/x/patch.diff?x=171cd95a600000
>

2019-08-21 14:41:16

by Alan Stern

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

On Wed, 21 Aug 2019, syzbot wrote:

> Hello,
>
> syzbot has tested the proposed patch but the reproducer still triggered
> crash:
> KASAN: slab-out-of-bounds Read in hidraw_ioctl
>
> ==================================================================
> BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
> Read of size 1 at addr ffff8881c8035f38 by task syz-executor.4/2833
>
> CPU: 1 PID: 2833 Comm: syz-executor.4 Not tainted 5.3.0-rc2+ #1
> 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+0xca/0x13e lib/dump_stack.c:113
> print_address_description+0x6a/0x32c mm/kasan/report.c:351
> __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
> kasan_report+0xe/0x12 mm/kasan/common.c:612
> strlen+0x79/0x90 lib/string.c:525
> strlen include/linux/string.h:281 [inline]
> hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
> vfs_ioctl fs/ioctl.c:46 [inline]
> file_ioctl fs/ioctl.c:509 [inline]
> do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
> ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
> __do_sys_ioctl fs/ioctl.c:720 [inline]
> __se_sys_ioctl fs/ioctl.c:718 [inline]
> __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
> do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x459829
> Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
> 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
> ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007f7a68f6dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
> RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
> RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7a68f6e6d4
> R13: 00000000004c21de R14: 00000000004d5620 R15: 00000000ffffffff
>
> Allocated by task 0:
> (stack is not available)
>
> Freed by task 0:
> (stack is not available)
>
> The buggy address belongs to the object at ffff8881c8035e60
> which belongs to the cache shmem_inode_cache of size 1168
> The buggy address is located 216 bytes inside of
> 1168-byte region [ffff8881c8035e60, ffff8881c80362f0)
> The buggy address belongs to the page:
> page:ffffea0007200d00 refcount:1 mapcount:0 mapping:ffff8881da115180
> index:0x0 compound_mapcount: 0
> flags: 0x200000000010200(slab|head)
> raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da115180
> raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
> page dumped because: kasan: bad access detected
>
> Memory state around the buggy address:
> ffff8881c8035e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881c8035e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > ffff8881c8035f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ^
> ffff8881c8035f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881c8036000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ==================================================================
>
>
> Tested on:
>
> commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
> git tree: https://github.com/google/kasan.git
> console output: https://syzkaller.appspot.com/x/log.txt?x=14f14a1e600000
> kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> patch: https://syzkaller.appspot.com/x/patch.diff?x=171cd95a600000

Get some debugging info:

#syz test: https://github.com/google/kasan.git e96407b4

Index: usb-devel/drivers/hid/hid-core.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-core.c
+++ usb-devel/drivers/hid/hid-core.c
@@ -1973,6 +1973,8 @@ int hid_hw_start(struct hid_device *hdev
{
int error;

+ dev_info(&hdev->dev, "In hid_hw_start for %p\n", hdev);
+ dump_stack();
error = hdev->ll_driver->start(hdev);
if (error)
return error;
@@ -1998,6 +2000,7 @@ EXPORT_SYMBOL_GPL(hid_hw_start);
*/
void hid_hw_stop(struct hid_device *hdev)
{
+ dev_info(&hdev->dev, "In hid_hw_stop for %p\n", hdev);
hid_disconnect(hdev);
hdev->ll_driver->stop(hdev);
}

2019-08-21 15:00:41

by Andrey Konovalov

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

On Sun, Aug 11, 2019 at 10:46 PM syzbot
<[email protected]> wrote:
>
> syzbot has found a reproducer for the following crash on:
>
> HEAD commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
> git tree: https://github.com/google/kasan.git usb-fuzzer
> console output: https://syzkaller.appspot.com/x/log.txt?x=150426ba600000
> kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> dashboard link: https://syzkaller.appspot.com/bug?extid=5a6c4ec678a0c6ee84ba
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12725c02600000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=162163c2600000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: [email protected]
>
> ==================================================================
> BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
> Read of size 1 at addr ffff8881d29bdf38 by task syz-executor201/1726
>
> CPU: 1 PID: 1726 Comm: syz-executor201 Not tainted 5.3.0-rc2+ #25
> 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+0xca/0x13e lib/dump_stack.c:113
> print_address_description+0x6a/0x32c mm/kasan/report.c:351
> __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
> kasan_report+0xe/0x12 mm/kasan/common.c:612
> strlen+0x79/0x90 lib/string.c:525
> strlen include/linux/string.h:281 [inline]
> hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
> vfs_ioctl fs/ioctl.c:46 [inline]
> file_ioctl fs/ioctl.c:509 [inline]
> do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
> ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
> __do_sys_ioctl fs/ioctl.c:720 [inline]
> __se_sys_ioctl fs/ioctl.c:718 [inline]
> __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
> do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x445679
> Code: e8 5c ad 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7
> 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
> ff 0f 83 9b cd fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007ffc8514f3a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445679
> RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
> RBP: 00000000006d0018 R08: 000000000000000b R09: 00000000004002e0
> R10: 000000000000000f R11: 0000000000000246 R12: 00000000004028a0
> R13: 0000000000402930 R14: 0000000000000000 R15: 0000000000000000
>
> Allocated by task 0:
> (stack is not available)
>
> Freed by task 0:
> (stack is not available)
>
> The buggy address belongs to the object at ffff8881d29bde60
> which belongs to the cache shmem_inode_cache of size 1168
> The buggy address is located 216 bytes inside of
> 1168-byte region [ffff8881d29bde60, ffff8881d29be2f0)
> The buggy address belongs to the page:
> page:ffffea00074a6f00 refcount:1 mapcount:0 mapping:ffff8881da115180
> index:0x0 compound_mapcount: 0
> flags: 0x200000000010200(slab|head)
> raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da115180
> raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
> page dumped because: kasan: bad access detected
>
> Memory state around the buggy address:
> ffff8881d29bde00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881d29bde80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > ffff8881d29bdf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ^
> ffff8881d29bdf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881d29be000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ==================================================================
>

Trying Alan's fix from another thread here:

#syz test: https://github.com/google/kasan.git usb-fuzzer e96407b4

Attachments:
logitech.patch (1.17 kB)

2019-08-21 15:00:42

by syzbot

[permalink] [raw]
Subject: Re: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

> On Sun, Aug 11, 2019 at 10:46 PM syzbot
> <[email protected]> wrote:

>> syzbot has found a reproducer for the following crash on:

>> HEAD commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
>> git tree: https://github.com/google/kasan.git usb-fuzzer
>> console output: https://syzkaller.appspot.com/x/log.txt?x=150426ba600000
>> kernel config:
>> https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
>> dashboard link:
>> https://syzkaller.appspot.com/bug?extid=5a6c4ec678a0c6ee84ba
>> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
>> syz repro:
>> https://syzkaller.appspot.com/x/repro.syz?x=12725c02600000
>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=162163c2600000

>> IMPORTANT: if you fix the bug, please add the following tag to the
>> commit:
>> Reported-by: [email protected]

>> ==================================================================
>> BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
>> Read of size 1 at addr ffff8881d29bdf38 by task syz-executor201/1726

>> CPU: 1 PID: 1726 Comm: syz-executor201 Not tainted 5.3.0-rc2+ #25
>> 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+0xca/0x13e lib/dump_stack.c:113
>> print_address_description+0x6a/0x32c mm/kasan/report.c:351
>> __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
>> kasan_report+0xe/0x12 mm/kasan/common.c:612
>> strlen+0x79/0x90 lib/string.c:525
>> strlen include/linux/string.h:281 [inline]
>> hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
>> vfs_ioctl fs/ioctl.c:46 [inline]
>> file_ioctl fs/ioctl.c:509 [inline]
>> do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
>> ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
>> __do_sys_ioctl fs/ioctl.c:720 [inline]
>> __se_sys_ioctl fs/ioctl.c:718 [inline]
>> __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
>> do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
>> entry_SYSCALL_64_after_hwframe+0x49/0xbe
>> RIP: 0033:0x445679
>> Code: e8 5c ad 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89
>> f7
>> 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
>> ff 0f 83 9b cd fb ff c3 66 2e 0f 1f 84 00 00 00 00
>> RSP: 002b:00007ffc8514f3a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
>> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445679
>> RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
>> RBP: 00000000006d0018 R08: 000000000000000b R09: 00000000004002e0
>> R10: 000000000000000f R11: 0000000000000246 R12: 00000000004028a0
>> R13: 0000000000402930 R14: 0000000000000000 R15: 0000000000000000

>> Allocated by task 0:
>> (stack is not available)

>> Freed by task 0:
>> (stack is not available)

>> The buggy address belongs to the object at ffff8881d29bde60
>> which belongs to the cache shmem_inode_cache of size 1168
>> The buggy address is located 216 bytes inside of
>> 1168-byte region [ffff8881d29bde60, ffff8881d29be2f0)
>> The buggy address belongs to the page:
>> page:ffffea00074a6f00 refcount:1 mapcount:0 mapping:ffff8881da115180
>> index:0x0 compound_mapcount: 0
>> flags: 0x200000000010200(slab|head)
>> raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da115180
>> raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
>> page dumped because: kasan: bad access detected

>> Memory state around the buggy address:
>> ffff8881d29bde00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> ffff8881d29bde80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> > ffff8881d29bdf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> ^
>> ffff8881d29bdf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> ffff8881d29be000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> ==================================================================


> Trying Alan's fix from another thread here:

> #syz test: https://github.com/google/kasan.git usb-fuzzer e96407b4

want 2 args (repo, branch), got 3

2019-08-21 15:14:13

by syzbot

[permalink] [raw]
Subject: Re: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

> On Sun, Aug 11, 2019 at 10:46 PM syzbot
> <[email protected]> wrote:

>> syzbot has found a reproducer for the following crash on:

>> HEAD commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
>> git tree: https://github.com/google/kasan.git usb-fuzzer
>> console output: https://syzkaller.appspot.com/x/log.txt?x=150426ba600000
>> kernel config:
>> https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
>> dashboard link:
>> https://syzkaller.appspot.com/bug?extid=5a6c4ec678a0c6ee84ba
>> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
>> syz repro:
>> https://syzkaller.appspot.com/x/repro.syz?x=12725c02600000
>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=162163c2600000

>> IMPORTANT: if you fix the bug, please add the following tag to the
>> commit:
>> Reported-by: [email protected]

>> ==================================================================
>> BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
>> Read of size 1 at addr ffff8881d29bdf38 by task syz-executor201/1726

>> CPU: 1 PID: 1726 Comm: syz-executor201 Not tainted 5.3.0-rc2+ #25
>> 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+0xca/0x13e lib/dump_stack.c:113
>> print_address_description+0x6a/0x32c mm/kasan/report.c:351
>> __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
>> kasan_report+0xe/0x12 mm/kasan/common.c:612
>> strlen+0x79/0x90 lib/string.c:525
>> strlen include/linux/string.h:281 [inline]
>> hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
>> vfs_ioctl fs/ioctl.c:46 [inline]
>> file_ioctl fs/ioctl.c:509 [inline]
>> do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
>> ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
>> __do_sys_ioctl fs/ioctl.c:720 [inline]
>> __se_sys_ioctl fs/ioctl.c:718 [inline]
>> __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
>> do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
>> entry_SYSCALL_64_after_hwframe+0x49/0xbe
>> RIP: 0033:0x445679
>> Code: e8 5c ad 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89
>> f7
>> 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
>> ff 0f 83 9b cd fb ff c3 66 2e 0f 1f 84 00 00 00 00
>> RSP: 002b:00007ffc8514f3a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
>> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445679
>> RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
>> RBP: 00000000006d0018 R08: 000000000000000b R09: 00000000004002e0
>> R10: 000000000000000f R11: 0000000000000246 R12: 00000000004028a0
>> R13: 0000000000402930 R14: 0000000000000000 R15: 0000000000000000

>> Allocated by task 0:
>> (stack is not available)

>> Freed by task 0:
>> (stack is not available)

>> The buggy address belongs to the object at ffff8881d29bde60
>> which belongs to the cache shmem_inode_cache of size 1168
>> The buggy address is located 216 bytes inside of
>> 1168-byte region [ffff8881d29bde60, ffff8881d29be2f0)
>> The buggy address belongs to the page:
>> page:ffffea00074a6f00 refcount:1 mapcount:0 mapping:ffff8881da115180
>> index:0x0 compound_mapcount: 0
>> flags: 0x200000000010200(slab|head)
>> raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da115180
>> raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
>> page dumped because: kasan: bad access detected

>> Memory state around the buggy address:
>> ffff8881d29bde00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> ffff8881d29bde80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> > ffff8881d29bdf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> ^
>> ffff8881d29bdf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> ffff8881d29be000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> ==================================================================


> Trying Alan's fix from another thread here:

> #syz test: https://github.com/google/kasan.git usb-fuzzer e96407b4

want 2 args (repo, branch), got 3


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2019-08-21 15:56:46

by Alan Stern

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

On Wed, 21 Aug 2019, syzbot wrote:

> Hello,
>
> syzbot has tested the proposed patch but the reproducer still triggered
> crash:
> KASAN: slab-out-of-bounds Read in hidraw_ioctl
>
> ==================================================================
> BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
> Read of size 1 at addr ffff8881d619df38 by task syz-executor.5/2984
>
> CPU: 0 PID: 2984 Comm: syz-executor.5 Not tainted 5.3.0-rc2+ #1
> 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+0xca/0x13e lib/dump_stack.c:113
> print_address_description+0x6a/0x32c mm/kasan/report.c:351
> __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
> kasan_report+0xe/0x12 mm/kasan/common.c:612
> strlen+0x79/0x90 lib/string.c:525
> strlen include/linux/string.h:281 [inline]
> hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
> vfs_ioctl fs/ioctl.c:46 [inline]
> file_ioctl fs/ioctl.c:509 [inline]
> do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
> ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
> __do_sys_ioctl fs/ioctl.c:720 [inline]
> __se_sys_ioctl fs/ioctl.c:718 [inline]
> __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
> do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x459829
> Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
> 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
> ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007f19881acc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
> RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
> RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 00007f19881ad6d4
> R13: 00000000004c21de R14: 00000000004d5620 R15: 00000000ffffffff

Looks like a test is missing in hidraw_ioctl.

Alan Stern

#syz test: https://github.com/google/kasan.git e96407b4

Index: usb-devel/drivers/hid/hidraw.c
===================================================================
--- usb-devel.orig/drivers/hid/hidraw.c
+++ usb-devel/drivers/hid/hidraw.c
@@ -370,7 +370,7 @@ static long hidraw_ioctl(struct file *fi

mutex_lock(&minors_lock);
dev = hidraw_table[minor];
- if (!dev) {
+ if (!dev || !dev->exist) {
ret = -ENODEV;
goto out;
}

2019-08-21 16:15:09

by syzbot

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger
crash:

Reported-and-tested-by:
[email protected]

Tested on:

commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git
kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
patch: https://syzkaller.appspot.com/x/patch.diff?x=13dca42e600000

Note: testing is done by a robot and is best-effort only.

2019-08-21 16:26:25

by Alan Stern

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

On Wed, 21 Aug 2019, Andrey Konovalov wrote:

> On Wed, Aug 21, 2019 at 3:37 PM syzbot
> <[email protected]> wrote:
> >
> > Hello,
> >
> > syzbot has tested the proposed patch but the reproducer still triggered
> > crash:
> > KASAN: slab-out-of-bounds Read in hidraw_ioctl
>
> Same here, a different bug.

It looks like I've got the fix for both these bugs. Testing now...

> > Tested on:
> >
> > commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
> > git tree: https://github.com/google/kasan.git
> > console output: https://syzkaller.appspot.com/x/log.txt?x=14f14a1e600000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> > compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> > patch: https://syzkaller.appspot.com/x/patch.diff?x=171cd95a600000

Why don't these patch-test reports include the dashboard link? It sure
would be handy to have a copy of it here.

Alan Stern

2019-08-21 16:27:54

by Andrey Konovalov

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

On Wed, Aug 21, 2019 at 6:24 PM Alan Stern <[email protected]> wrote:
>
> On Wed, 21 Aug 2019, Andrey Konovalov wrote:
>
> > On Wed, Aug 21, 2019 at 3:37 PM syzbot
> > <[email protected]> wrote:
> > >
> > > Hello,
> > >
> > > syzbot has tested the proposed patch but the reproducer still triggered
> > > crash:
> > > KASAN: slab-out-of-bounds Read in hidraw_ioctl
> >
> > Same here, a different bug.
>
> It looks like I've got the fix for both these bugs. Testing now...

Great! Do you think "BUG: bad usercopy in hidraw_ioctl" can also be
fixed by one of those fixes?

>
> > > Tested on:
> > >
> > > commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
> > > git tree: https://github.com/google/kasan.git
> > > console output: https://syzkaller.appspot.com/x/log.txt?x=14f14a1e600000
> > > kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> > > compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> > > patch: https://syzkaller.appspot.com/x/patch.diff?x=171cd95a600000
>
> Why don't these patch-test reports include the dashboard link? It sure
> would be handy to have a copy of it here.
>
> Alan Stern
>

2019-08-21 16:51:57

by Andrey Konovalov

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

On Wed, Aug 21, 2019 at 6:26 PM Andrey Konovalov <[email protected]> wrote:
>
> On Wed, Aug 21, 2019 at 6:24 PM Alan Stern <[email protected]> wrote:
> >
> > On Wed, 21 Aug 2019, Andrey Konovalov wrote:
> >
> > > On Wed, Aug 21, 2019 at 3:37 PM syzbot
> > > <[email protected]> wrote:
> > > >
> > > > Hello,
> > > >
> > > > syzbot has tested the proposed patch but the reproducer still triggered
> > > > crash:
> > > > KASAN: slab-out-of-bounds Read in hidraw_ioctl
> > >
> > > Same here, a different bug.
> >
> > It looks like I've got the fix for both these bugs. Testing now...
>
> Great! Do you think "BUG: bad usercopy in hidraw_ioctl" can also be
> fixed by one of those fixes?

We actually have a bunch of other non reproducible bug reports that
come from HID. I think I'll dup them into these two bugs that you've
fixed, and we'll see if syzkaller triggers them again once the fixes
are upstream.

>
> >
> > > > Tested on:
> > > >
> > > > commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
> > > > git tree: https://github.com/google/kasan.git
> > > > console output: https://syzkaller.appspot.com/x/log.txt?x=14f14a1e600000
> > > > kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> > > > compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> > > > patch: https://syzkaller.appspot.com/x/patch.diff?x=171cd95a600000
> >
> > Why don't these patch-test reports include the dashboard link? It sure
> > would be handy to have a copy of it here.

Sorry, didn't notice this comment. This should be easy to implement,
I'll look into that, thanks!

2019-08-21 17:10:03

by syzbot

[permalink] [raw]
Subject: Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

Hello,

syzbot has tested the proposed patch but the reproducer still triggered
crash:
KASAN: slab-out-of-bounds Read in hidraw_ioctl

==================================================================
BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
Read of size 1 at addr ffff8881d619df38 by task syz-executor.5/2984

CPU: 0 PID: 2984 Comm: syz-executor.5 Not tainted 5.3.0-rc2+ #1
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+0xca/0x13e lib/dump_stack.c:113
print_address_description+0x6a/0x32c mm/kasan/report.c:351
__kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
kasan_report+0xe/0x12 mm/kasan/common.c:612
strlen+0x79/0x90 lib/string.c:525
strlen include/linux/string.h:281 [inline]
hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f19881acc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f19881ad6d4
R13: 00000000004c21de R14: 00000000004d5620 R15: 00000000ffffffff

Allocated by task 1607:
save_stack+0x1b/0x80 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_kmalloc mm/kasan/common.c:487 [inline]
__kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:460
kmalloc include/linux/slab.h:552 [inline]
syslog_print kernel/printk/printk.c:1346 [inline]
do_syslog kernel/printk/printk.c:1519 [inline]
do_syslog+0x540/0x1380 kernel/printk/printk.c:1493
kmsg_read+0x8a/0xb0 fs/proc/kmsg.c:40
proc_reg_read+0x1c1/0x280 fs/proc/inode.c:223
__vfs_read+0x76/0x100 fs/read_write.c:425
vfs_read+0x1ea/0x430 fs/read_write.c:461
ksys_read+0x127/0x250 fs/read_write.c:587
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 1607:
save_stack+0x1b/0x80 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_slab_free+0x130/0x180 mm/kasan/common.c:449
slab_free_hook mm/slub.c:1423 [inline]
slab_free_freelist_hook mm/slub.c:1470 [inline]
slab_free mm/slub.c:3012 [inline]
kfree+0xe4/0x2f0 mm/slub.c:3953
syslog_print kernel/printk/printk.c:1405 [inline]
do_syslog kernel/printk/printk.c:1519 [inline]
do_syslog+0x1098/0x1380 kernel/printk/printk.c:1493
kmsg_read+0x8a/0xb0 fs/proc/kmsg.c:40
proc_reg_read+0x1c1/0x280 fs/proc/inode.c:223
__vfs_read+0x76/0x100 fs/read_write.c:425
vfs_read+0x1ea/0x430 fs/read_write.c:461
ksys_read+0x127/0x250 fs/read_write.c:587
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881d619db00
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 56 bytes to the right of
1024-byte region [ffff8881d619db00, ffff8881d619df00)
The buggy address belongs to the page:
page:ffffea0007586700 refcount:1 mapcount:0 mapping:ffff8881da002280
index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da002280
raw: 0000000000000000 00000000000e000e 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff8881d619de00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8881d619de80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8881d619df00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8881d619df80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8881d619e000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


Tested on:

commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git
console output: https://syzkaller.appspot.com/x/log.txt?x=1138542e600000
kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
patch: https://syzkaller.appspot.com/x/patch.diff?x=1197b996600000

2019-08-21 17:58:43

by Alan Stern

[permalink] [raw]
Subject: [PATCH] HID: hidraw: Fix invalid read in hidraw_ioctl

The syzbot fuzzer has reported a pair of problems in the
hidraw_ioctl() function: slab-out-of-bounds read and use-after-free
read. An example of the first:

BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
Read of size 1 at addr ffff8881c8035f38 by task syz-executor.4/2833

CPU: 1 PID: 2833 Comm: syz-executor.4 Not tainted 5.3.0-rc2+ #1
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+0xca/0x13e lib/dump_stack.c:113
print_address_description+0x6a/0x32c mm/kasan/report.c:351
__kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
kasan_report+0xe/0x12 mm/kasan/common.c:612
strlen+0x79/0x90 lib/string.c:525
strlen include/linux/string.h:281 [inline]
hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f7a68f6dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7a68f6e6d4
R13: 00000000004c21de R14: 00000000004d5620 R15: 00000000ffffffff

The two problems have the same cause: hidraw_ioctl() fails to test
whether the device has been removed. This patch adds the missing test.

Reported-and-tested-by: [email protected]
Signed-off-by: Alan Stern <[email protected]>
CC: <[email protected]>

---


[as1910.hidraw-ioctl-fix]


drivers/hid/hidraw.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

Index: usb-devel/drivers/hid/hidraw.c
===================================================================
--- usb-devel.orig/drivers/hid/hidraw.c
+++ usb-devel/drivers/hid/hidraw.c
@@ -370,7 +370,7 @@ static long hidraw_ioctl(struct file *fi

mutex_lock(&minors_lock);
dev = hidraw_table[minor];
- if (!dev) {
+ if (!dev || !dev->exist) {
ret = -ENODEV;
goto out;
}

2019-08-22 08:49:51

by Jiri Kosina

[permalink] [raw]
Subject: Re: [PATCH] HID: hidraw: Fix invalid read in hidraw_ioctl

On Wed, 21 Aug 2019, Alan Stern wrote:

> The syzbot fuzzer has reported a pair of problems in the
> hidraw_ioctl() function: slab-out-of-bounds read and use-after-free
> read. An example of the first:
>
> BUG: KASAN: slab-out-of-bounds in strlen+0x79/0x90 lib/string.c:525
> Read of size 1 at addr ffff8881c8035f38 by task syz-executor.4/2833
>
> CPU: 1 PID: 2833 Comm: syz-executor.4 Not tainted 5.3.0-rc2+ #1
> 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+0xca/0x13e lib/dump_stack.c:113
> print_address_description+0x6a/0x32c mm/kasan/report.c:351
> __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
> kasan_report+0xe/0x12 mm/kasan/common.c:612
> strlen+0x79/0x90 lib/string.c:525
> strlen include/linux/string.h:281 [inline]
> hidraw_ioctl+0x245/0xae0 drivers/hid/hidraw.c:446
> vfs_ioctl fs/ioctl.c:46 [inline]
> file_ioctl fs/ioctl.c:509 [inline]
> do_vfs_ioctl+0xd2d/0x1330 fs/ioctl.c:696
> ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
> __do_sys_ioctl fs/ioctl.c:720 [inline]
> __se_sys_ioctl fs/ioctl.c:718 [inline]
> __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
> do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x459829
> Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
> 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
> ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007f7a68f6dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
> RDX: 0000000000000000 RSI: 0000000080404805 RDI: 0000000000000004
> RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7a68f6e6d4
> R13: 00000000004c21de R14: 00000000004d5620 R15: 00000000ffffffff
>
> The two problems have the same cause: hidraw_ioctl() fails to test
> whether the device has been removed. This patch adds the missing test.
>
> Reported-and-tested-by: [email protected]
> Signed-off-by: Alan Stern <[email protected]>

Thanks a lot Alan for chasing this; I've applied the patch.

--
Jiri Kosina
SUSE Labs