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BUG: KASAN: use-after-free in string+0x208/0x230 lib/vsprintf.c:606
Read of size 1 at addr ffff888090dcec40 by task syz-executor.4/16093
CPU: 1 PID: 16093 Comm: syz-executor.4 Not tainted 5.0.0+ #18
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+0x172/0x1f0 lib/dump_stack.c:113
print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
__asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:129
string+0x208/0x230 lib/vsprintf.c:606
vsnprintf+0xbfc/0x1af0 lib/vsprintf.c:2396
add_uevent_var+0x14d/0x310 lib/kobject_uevent.c:661
input_dev_uevent+0x163/0x890 drivers/input/input.c:1594
dev_uevent+0x312/0x580 drivers/base/core.c:1180
kobject_uevent_env+0x487/0x1030 lib/kobject_uevent.c:549
kobject_uevent+0x20/0x26 lib/kobject_uevent.c:638
kobject_cleanup lib/kobject.c:649 [inline]
kobject_release lib/kobject.c:691 [inline]
kref_put include/linux/kref.h:67 [inline]
kobject_put.cold+0x177/0x2ec lib/kobject.c:708
put_device+0x20/0x30 drivers/base/core.c:2205
input_put_device include/linux/input.h:349 [inline]
evdev_free+0x51/0x70 drivers/input/evdev.c:369
device_release+0x7d/0x210 drivers/base/core.c:1064
kobject_cleanup lib/kobject.c:662 [inline]
kobject_release lib/kobject.c:691 [inline]
kref_put include/linux/kref.h:67 [inline]
kobject_put.cold+0x28f/0x2ec lib/kobject.c:708
cdev_default_release+0x41/0x50 fs/char_dev.c:607
kobject_cleanup lib/kobject.c:662 [inline]
kobject_release lib/kobject.c:691 [inline]
kref_put include/linux/kref.h:67 [inline]
kobject_put.cold+0x28f/0x2ec lib/kobject.c:708
cdev_put.part.0+0x39/0x50 fs/char_dev.c:368
cdev_put fs/char_dev.c:366 [inline]
chrdev_open+0x2c3/0x6b0 fs/char_dev.c:425
do_dentry_open+0x488/0x1160 fs/open.c:771
vfs_open+0xa0/0xd0 fs/open.c:880
do_last fs/namei.c:3416 [inline]
path_openat+0x10e9/0x46e0 fs/namei.c:3533
do_filp_open+0x1a1/0x280 fs/namei.c:3563
do_sys_open+0x3fe/0x5d0 fs/open.c:1063
__do_sys_open fs/open.c:1081 [inline]
__se_sys_open fs/open.c:1076 [inline]
__x64_sys_open+0x7e/0xc0 fs/open.c:1076
do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x412011
Code: 75 14 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 b4 17 00 00 c3 48 83 ec 08 e8 2a fa ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 73 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007fb66492a7a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000412011
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007fb66492a850
RBP: 000000000073bf00 R08: 000000000000000f R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007fb66492b6d4
R13: 00000000004c6a33 R14: 00000000004dc030 R15: 00000000ffffffff
Allocated by task 15982:
save_stack+0x45/0xd0 mm/kasan/common.c:75
set_track mm/kasan/common.c:87 [inline]
__kasan_kmalloc mm/kasan/common.c:497 [inline]
__kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470
kasan_kmalloc+0x9/0x10 mm/kasan/common.c:511
__do_kmalloc mm/slab.c:3726 [inline]
__kmalloc_track_caller+0x158/0x740 mm/slab.c:3741
kstrndup+0x5f/0xf0 mm/util.c:96
uinput_dev_setup+0x1d4/0x310 drivers/input/misc/uinput.c:475
uinput_ioctl_handler.isra.0+0x12b8/0x1cc0 drivers/input/misc/uinput.c:886
uinput_ioctl+0x4a/0x60 drivers/input/misc/uinput.c:1049
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Freed by task 15982:
save_stack+0x45/0xd0 mm/kasan/common.c:75
set_track mm/kasan/common.c:87 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/common.c:459
kasan_slab_free+0xe/0x10 mm/kasan/common.c:467
__cache_free mm/slab.c:3498 [inline]
kfree+0xcf/0x230 mm/slab.c:3821
uinput_destroy_device+0xf8/0x250 drivers/input/misc/uinput.c:311
uinput_ioctl_handler.isra.0+0x886/0x1cc0 drivers/input/misc/uinput.c:882
uinput_ioctl+0x4a/0x60 drivers/input/misc/uinput.c:1049
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
The buggy address belongs to the object at ffff888090dcec40
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
32-byte region [ffff888090dcec40, ffff888090dcec60)
The buggy address belongs to the page:
page:ffffea0002437380 count:1 mapcount:0 mapping:ffff88812c3f01c0 index:0xffff888090dcefc1
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea000257b0c8 ffffea00026fae48 ffff88812c3f01c0
raw: ffff888090dcefc1 ffff888090dce000 000000010000003f 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff888090dceb00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
ffff888090dceb80: 00 00 02 fc fc fc fc fc fb fb fb fb fc fc fc fc
>ffff888090dcec00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
^
ffff888090dcec80: fb fb fb fb fc fc fc fc 00 04 fc fc fc fc fc fc
ffff888090dced00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
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