syzbot

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BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
BUG: KASAN: use-after-free in atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:575 [inline]
BUG: KASAN: use-after-free in netdev_run_todo+0xdfb/0xf40 net/core/dev.c:10409
Write of size 4 at addr ffff88807e0e8048 by task syz-executor/14471

CPU: 1 PID: 14471 Comm: syz-executor Not tainted 6.1.112-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 kasan_check_range+0x27f/0x290 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
 atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:575 [inline]
 netdev_run_todo+0xdfb/0xf40 net/core/dev.c:10409
 nsim_destroy+0xac/0x140 drivers/net/netdevsim/netdev.c:387
 __nsim_dev_port_del+0x153/0x1b0 drivers/net/netdevsim/dev.c:1430
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1442 [inline]
 nsim_dev_reload_destroy+0x286/0x490 drivers/net/netdevsim/dev.c:1659
 nsim_drv_remove+0x5c/0x160 drivers/net/netdevsim/dev.c:1675
 device_remove drivers/base/dd.c:548 [inline]
 __device_release_driver drivers/base/dd.c:1260 [inline]
 device_release_driver_internal+0x4f3/0x880 drivers/base/dd.c:1286
 bus_remove_device+0x2e5/0x400 drivers/base/bus.c:529
 device_del+0x6e2/0xbd0 drivers/base/core.c:3880
 device_unregister+0x1c/0xc0 drivers/base/core.c:3923
 nsim_bus_dev_del drivers/net/netdevsim/bus.c:310 [inline]
 del_device_store+0x35f/0x480 drivers/net/netdevsim/bus.c:219
 kernfs_fop_write_iter+0x3a2/0x4f0 fs/kernfs/file.c:334
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x857/0xbc0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fee5db7cadf
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 1c 8e 02 00 48
RSP: 002b:00007ffcc6208930 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fee5db7cadf
RDX: 0000000000000001 RSI: 00007ffcc6208980 RDI: 0000000000000005
RBP: 00007fee5dbf13ae R08: 0000000000000000 R09: 00007ffcc6208787
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffcc6208980 R14: 00007fee5e864620 R15: 0000000000000003
 </TASK>

Allocated by task 5388:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
 kmem_cache_zalloc include/linux/slab.h:683 [inline]
 net_alloc net/core/net_namespace.c:413 [inline]
 copy_net_ns+0x140/0x5d0 net/core/net_namespace.c:468
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
 ksys_unshare+0x580/0xb20 kernel/fork.c:3203
 __do_sys_unshare kernel/fork.c:3274 [inline]
 __se_sys_unshare kernel/fork.c:3272 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3272
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 6637:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x292/0x510 mm/slub.c:3683
 net_free net/core/net_namespace.c:442 [inline]
 cleanup_net+0xab5/0xb60 net/core/net_namespace.c:625
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 insert_work+0x54/0x3d0 kernel/workqueue.c:1361
 __queue_work+0xb4b/0xf90 kernel/workqueue.c:1520
 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1544 [inline]
 __run_timers+0x6a8/0x890 kernel/time/timer.c:1820
 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
 __do_softirq kernel/softirq.c:605 [inline]
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:654
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:666
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653

Second to last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 insert_work+0x54/0x3d0 kernel/workqueue.c:1361
 __queue_work+0xb4b/0xf90 kernel/workqueue.c:1520
 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1544 [inline]
 __run_timers+0x6a8/0x890 kernel/time/timer.c:1820
 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
 __do_softirq kernel/softirq.c:605 [inline]
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:654
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:666
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653

The buggy address belongs to the object at ffff88807e0e8000
 which belongs to the cache net_namespace of size 6976
The buggy address is located 72 bytes inside of
 6976-byte region [ffff88807e0e8000, ffff88807e0e9b40)

The buggy address belongs to the physical page:
page:ffffea0001f83a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e0e8
head:ffffea0001f83a00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff88807d7bf501
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001e10400 dead000000000002 ffff888140009500
raw: 0000000000000000 0000000080040004 00000001ffffffff ffff88807d7bf501
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4810, tgid 4807 (syz.3.427), ts 106248785275, free_ts 106232455635
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 prep_new_page mm/page_alloc.c:2524 [inline]
 get_page_from_freelist+0x322e/0x33b0 mm/page_alloc.c:4290
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5558
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x1a5/0x2d0 mm/slub.c:3422
 kmem_cache_zalloc include/linux/slab.h:683 [inline]
 net_alloc net/core/net_namespace.c:413 [inline]
 copy_net_ns+0x140/0x5d0 net/core/net_namespace.c:468
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 copy_namespaces+0x397/0x3f0 kernel/nsproxy.c:178
 copy_process+0x1ab8/0x4060 kernel/fork.c:2270
 kernel_clone+0x222/0x920 kernel/fork.c:2682
 __do_sys_clone kernel/fork.c:2823 [inline]
 __se_sys_clone kernel/fork.c:2807 [inline]
 __x64_sys_clone+0x231/0x280 kernel/fork.c:2807
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1444 [inline]
 free_pcp_prepare mm/page_alloc.c:1494 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3464
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2586
 put_cpu_partial+0x17b/0x250 mm/slub.c:2662
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
 getname_flags+0xb8/0x4f0 fs/namei.c:139
 vfs_fstatat fs/stat.c:266 [inline]
 __do_sys_newfstatat fs/stat.c:437 [inline]
 __se_sys_newfstatat fs/stat.c:431 [inline]
 __x64_sys_newfstatat+0x130/0x1e0 fs/stat.c:431
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff88807e0e7f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807e0e7f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807e0e8000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff88807e0e8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807e0e8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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