syzbot has found a reproducer for the following crash on:
HEAD commit:629f8205 Merge tag 'for-linus-20190730' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11a2774460
kernel config: https://syzkaller.appspot.com/x/.config?x=4c7b914a2680c9c6
dashboard link: https://syzkaller.appspot.com/bug?extid=107429d62fb1d293602f
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16a7c8dc60
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1498cfa260
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+107429d62fb1d2936...@syzkaller.appspotmail.com
==
BUG: KASAN: use-after-free in debug_spin_lock_before
kernel/locking/spinlock_debug.c:83 [inline]
BUG: KASAN: use-after-free in do_raw_spin_lock+0x28a/0x2e0
kernel/locking/spinlock_debug.c:112
Read of size 4 at addr 8880a81b540c by task syz-executor143/10205
CPU: 1 PID: 10205 Comm: syz-executor143 Not tainted 5.3.0-rc2+ #90
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+0xd4/0x306 mm/kasan/report.c:351
__kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482
kasan_report+0x12/0x17 mm/kasan/common.c:612
__asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]
do_raw_spin_lock+0x28a/0x2e0 kernel/locking/spinlock_debug.c:112
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
_raw_spin_lock_bh+0x3b/0x50 kernel/locking/spinlock.c:175
spin_lock_bh include/linux/spinlock.h:343 [inline]
release_sock+0x20/0x1c0 net/core/sock.c:2932
nr_release+0x303/0x3e0 net/netrom/af_netrom.c:553
__sock_release+0xce/0x280 net/socket.c:590
sock_close+0x1e/0x30 net/socket.c:1268
__fput+0x2ff/0x890 fs/file_table.c:280
fput+0x16/0x20 fs/file_table.c:313
task_work_run+0x145/0x1c0 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0x92f/0x2e50 kernel/exit.c:879
do_group_exit+0x135/0x360 kernel/exit.c:983
get_signal+0x47c/0x2500 kernel/signal.c:2729
do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815
exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159
prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
do_syscall_64+0x5a9/0x6a0 arch/x86/entry/common.c:299
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x447d09
Code: Bad RIP value.
RSP: 002b:7fca48b63db8 EFLAGS: 0246 ORIG_RAX: 002b
RAX: fe00 RBX: 006ddc58 RCX: 00447d09
RDX: RSI: RDI: 0007
RBP: 006ddc50 R08: R09:
R10: R11: 0246 R12: 006ddc5c
R13: 7ffe913f3ebf R14: 7fca48b649c0 R15: 0001
Allocated by task 0:
save_stack+0x23/0x90 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+0xcf/0xe0 mm/kasan/common.c:460
kasan_kmalloc+0x9/0x10 mm/kasan/common.c:501
__do_kmalloc mm/slab.c:3655 [inline]
__kmalloc+0x163/0x770 mm/slab.c:3664
kmalloc include/linux/slab.h:557 [inline]
sk_prot_alloc+0x23a/0x310 net/core/sock.c:1603
sk_alloc+0x39/0xf70 net/core/sock.c:1657
nr_make_new net/netrom/af_netrom.c:476 [inline]
nr_rx_frame+0x733/0x1e73 net/netrom/af_netrom.c:959
nr_loopback_timer+0x7b/0x170 net/netrom/nr_loopback.c:59
call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322
expire_timers kernel/time/timer.c:1366 [inline]
__run_timers kernel/time/timer.c:1685 [inline]
__run_timers kernel/time/timer.c:1653 [inline]
run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698
__do_softirq+0x262/0x98c kernel/softirq.c:292
Freed by task 10205:
save_stack+0x23/0x90 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/common.c:449
kasan_slab_free+0xe/0x10 mm/kasan/common.c:457
__cache_free mm/slab.c:3425 [inline]
kfree+0x10a/0x2c0 mm/slab.c:3756
sk_prot_free net/core/sock.c:1640 [inline]
__sk_destruct+0x4f7/0x6e0 net/core/sock.c:1726
sk_destruct+0x86/0xa0 net/core/sock.c:1734
__sk_free+0xfb/0x360 net/core/sock.c:1745
sk_free+0x42/0x50 net/core/sock.c:1756
sock_put include/net/sock.h:1725 [inline]
nr_destroy_socket+0x3ea/0x4a0 net/netrom/af_netrom.c:288
nr_release+0x347/0x3e0 net/netrom/af_netrom.c:530
__sock_release+0xce/0x280 net/socket.c:590
sock_close+0x1e/0x30 net/socket.c:1268
__fput+0x2ff/0x890 fs/file_table.c:280
fput+0x16/0x20 fs/file_table.c:313
task_work_run+0x145/0x1c0 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
