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BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:185 [inline]
BUG: KASAN: use-after-free in atomic_read arch/x86/include/asm/atomic.h:27 [inline]
BUG: KASAN: use-after-free in refcount_dec_not_one+0x9a/0xc0 lib/refcount.c:270
Read of size 4 at addr ffff8880abc8a698 by task systemd-udevd/5286
CPU: 0 PID: 5286 Comm: systemd-udevd Not tainted 4.14.302-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x281 lib/dump_stack.c:58
print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351
kasan_report mm/kasan/report.c:409 [inline]
__asan_report_load4_noabort+0x68/0x70 mm/kasan/report.c:429
__read_once_size include/linux/compiler.h:185 [inline]
atomic_read arch/x86/include/asm/atomic.h:27 [inline]
refcount_dec_not_one+0x9a/0xc0 lib/refcount.c:270
refcount_dec_and_mutex_lock+0x1a/0x60 lib/refcount.c:309
nbd_put drivers/block/nbd.c:228 [inline]
nbd_release+0xf3/0x150 drivers/block/nbd.c:1454
__blkdev_put+0x5aa/0x800 fs/block_dev.c:1803
blkdev_close+0x86/0xb0 fs/block_dev.c:1875
__fput+0x25f/0x7a0 fs/file_table.c:210
task_work_run+0x11f/0x190 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:191 [inline]
exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164
prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7fc7400a6270
RSP: 002b:00007fff5038b658 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fc7400a6270
RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 00007fc740f60710 R08: 000000000000004a R09: 0000000000000008
R10: 000055bf41a211b8 R11: 0000000000000246 R12: 0000000000000000
R13: 000055bf41a1c6e0 R14: 0000000000000003 R15: 000000000000000e
Allocated by task 5279:
save_stack mm/kasan/kasan.c:447 [inline]
set_track mm/kasan/kasan.c:459 [inline]
kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551
kmem_cache_alloc_trace+0x131/0x3d0 mm/slab.c:3618
kmalloc include/linux/slab.h:488 [inline]
kzalloc include/linux/slab.h:661 [inline]
nbd_dev_add+0x7c/0x800 drivers/block/nbd.c:1619
nbd_genl_connect+0x3a4/0x13e0 drivers/block/nbd.c:1764
genl_family_rcv_msg+0x572/0xb20 net/netlink/genetlink.c:600
genl_rcv_msg+0xaf/0x140 net/netlink/genetlink.c:625
netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2454
genl_rcv+0x24/0x40 net/netlink/genetlink.c:636
netlink_unicast_kernel net/netlink/af_netlink.c:1296 [inline]
netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1322
netlink_sendmsg+0x648/0xbc0 net/netlink/af_netlink.c:1893
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xb5/0x100 net/socket.c:656
___sys_sendmsg+0x6c8/0x800 net/socket.c:2062
__sys_sendmsg+0xa3/0x120 net/socket.c:2096
SYSC_sendmsg net/socket.c:2107 [inline]
SyS_sendmsg+0x27/0x40 net/socket.c:2103
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x5e/0xd3
Freed by task 5286:
save_stack mm/kasan/kasan.c:447 [inline]
set_track mm/kasan/kasan.c:459 [inline]
kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524
__cache_free mm/slab.c:3496 [inline]
kfree+0xc9/0x250 mm/slab.c:3815
nbd_dev_remove drivers/block/nbd.c:223 [inline]
nbd_put.part.0+0x100/0x140 drivers/block/nbd.c:231
nbd_put drivers/block/nbd.c:267 [inline]
nbd_config_put+0x51c/0x6c0 drivers/block/nbd.c:1172
nbd_release+0xdf/0x150 drivers/block/nbd.c:1453
__blkdev_put+0x5aa/0x800 fs/block_dev.c:1803
blkdev_close+0x86/0xb0 fs/block_dev.c:1875
__fput+0x25f/0x7a0 fs/file_table.c:210
task_work_run+0x11f/0x190 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:191 [inline]
exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164
prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
entry_SYSCALL_64_after_hwframe+0x5e/0xd3
The buggy address belongs to the object at ffff8880abc8a5c0
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 216 bytes inside of
512-byte region [ffff8880abc8a5c0, ffff8880abc8a7c0)
The buggy address belongs to the page:
page:ffffea0002af2280 count:1 mapcount:0 mapping:ffff8880abc8a0c0 index:0xffff8880abc8ad40
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffff8880abc8a0c0 ffff8880abc8ad40 0000000100000004
raw: ffffea000255fae0 ffffea00026b52a0 ffff88813fe74940 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8880abc8a580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
ffff8880abc8a600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880abc8a680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880abc8a700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880abc8a780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
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