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BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: null-ptr-deref in atomic_add_negative_release include/linux/atomic/atomic-instrumented.h:1457 [inline]
BUG: KASAN: null-ptr-deref in __rcuref_put include/linux/rcuref.h:87 [inline]
BUG: KASAN: null-ptr-deref in rcuref_put include/linux/rcuref.h:150 [inline]
BUG: KASAN: null-ptr-deref in dst_release+0x4e/0x1e0 net/core/dst.c:164
Write of size 4 at addr 0000000000000043 by task kworker/u32:1/13

CPU: 3 PID: 13 Comm: kworker/u32:1 Not tainted 6.10.0-rc1-syzkaller-00013-g2bfcfd584ff5 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
 atomic_add_negative_release include/linux/atomic/atomic-instrumented.h:1457 [inline]
 __rcuref_put include/linux/rcuref.h:87 [inline]
 rcuref_put include/linux/rcuref.h:150 [inline]
 dst_release+0x4e/0x1e0 net/core/dst.c:164
 dst_cache_destroy net/core/dst_cache.c:161 [inline]
 dst_cache_destroy+0x11c/0x270 net/core/dst_cache.c:153
 ip_tunnel_dev_free+0x25/0x60 net/ipv4/ip_tunnel.c:1101
 netdev_run_todo+0x775/0x1250 net/core/dev.c:10692
 cleanup_net+0x591/0xbf0 net/core/net_namespace.c:636
 process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
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