[v5.15] WARNING: refcount bug in sctp_transport_put

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 00c03985402e Linux 5.15.136
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=111ce55d680000
kernel config: https://syzkaller.appspot.com/x/.config?x=44f1119854f35733
dashboard link: https://syzkaller.appspot.com/bug?extid=7ab8d948f0020c67569a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8b6792bef09d/disk-00c03985.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d63de1cd585e/vmlinux-00c03985.xz
kernel image: https://storage.googleapis.com/syzbot-assets/90e251933a79/Image-00c03985.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7ab8d9...@syzkaller.appspotmail.com

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refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 9345 at lib/refcount.c:28 refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28
Modules linked in:
CPU: 1 PID: 9345 Comm: modprobe Not tainted 5.15.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28
lr : refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28
sp : ffff800008017a90
x29: ffff800008017a90 x28: 1fffe00018ceb001 x27: ffff0000da9cec00
x26: dfff800000000000 x25: ffff80001490d310 x24: 0000000000000001
x23: ffff0000c8bc0000 x22: ffff0000d0d14000 x21: 0000000000000003
x20: ffff0000f8beb820 x19: ffff800016d12000 x18: 0000000000000101
x17: ff80800008335cb8 x16: ffff80001196bde4 x15: ffff800008335cb8
x14: 00000000ffffffff x13: ffffffffffffffff x12: 0000000000000100
x11: ff8080000832d7ac x10: 0000000000000000 x9 : f778a67a3b9b7900
x8 : f778a67a3b9b7900 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000080171f8 x4 : ffff8000149ef860 x3 : ffff80000854fe18
x2 : 0000000000000001 x1 : 0000000000000100 x0 : 0000000000000026
Call trace:
refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28
__refcount_sub_and_test include/linux/refcount.h:283 [inline]
__refcount_dec_and_test include/linux/refcount.h:315 [inline]
refcount_dec_and_test include/linux/refcount.h:333 [inline]
sctp_transport_put+0x138/0x188 net/sctp/transport.c:489
sctp_generate_heartbeat_event+0x304/0x3dc net/sctp/sm_sideeffect.c:401
call_timer_fn+0x19c/0x8f0 kernel/time/timer.c:1421
expire_timers kernel/time/timer.c:1466 [inline]
__run_timers+0x554/0x718 kernel/time/timer.c:1737
run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1750
__do_softirq+0x344/0xe20 kernel/softirq.c:558
do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline]
invoke_softirq kernel/softirq.c:439 [inline]
__irq_exit_rcu+0x28c/0x534 kernel/softirq.c:637
irq_exit+0x14/0x88 kernel/softirq.c:661
handle_domain_irq+0xf4/0x178 kernel/irq/irqdesc.c:710
gic_handle_irq+0x78/0x1c8 drivers/irqchip/irq-gic-v3.c:758
call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:899
do_interrupt_handler+0x74/0x94 arch/arm64/kernel/entry-common.c:267
el1_interrupt+0x30/0x58 arch/arm64/kernel/entry-common.c:454
el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:470
el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:580
stackdepot_memcmp lib/stackdepot.c:194 [inline]
find_stack lib/stackdepot.c:210 [inline]
stack_depot_save+0x1d0/0x4a0 lib/stackdepot.c:280
kasan_save_stack mm/kasan/common.c:40 [inline]
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
__kasan_slab_alloc+0xa8/0xcc mm/kasan/common.c:467
kasan_slab_alloc include/linux/kasan.h:254 [inline]
slab_post_alloc_hook+0x74/0x3f4 mm/slab.h:519
slab_alloc_node mm/slub.c:3220 [inline]
slab_alloc mm/slub.c:3228 [inline]
kmem_cache_alloc+0x1dc/0x45c mm/slub.c:3233
kmem_cache_zalloc include/linux/slab.h:711 [inline]
lsm_file_alloc security/security.c:574 [inline]
security_file_alloc+0x30/0x124 security/security.c:1530
__alloc_file+0xb0/0x240 fs/file_table.c:106
alloc_empty_file+0xa8/0x198 fs/file_table.c:150
path_openat+0xdc/0x26f0 fs/namei.c:3658
do_filp_open+0x1a8/0x3b4 fs/namei.c:3699
do_sys_openat2+0x128/0x3d8 fs/open.c:1211
do_sys_open fs/open.c:1227 [inline]
__do_sys_openat fs/open.c:1243 [inline]
__se_sys_openat fs/open.c:1238 [inline]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1238
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
irq event stamp: 1031
hardirqs last enabled at (1030): [<ffff80000832b944>] __up_console_sem+0xb4/0x100 kernel/printk/printk.c:257
hardirqs last disabled at (1031): [<ffff800011967470>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:396
softirqs last enabled at (776): [<ffff8000080300b4>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:31
softirqs last disabled at (987): [<ffff8000081b5750>] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline]
softirqs last disabled at (987): [<ffff8000081b5750>] invoke_softirq kernel/softirq.c:439 [inline]
softirqs last disabled at (987): [<ffff8000081b5750>] __irq_exit_rcu+0x28c/0x534 kernel/softirq.c:637
---[ end trace 33dc4df5e982ab18 ]---


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.