================================================================== BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:384 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0x882/0x9c0 net/ipv4/tcp_timer.c:648 Read of size 1 at addr ffff888078ba3b8d by task kworker/0:9/3581 CPU: 0 PID: 3581 Comm: kworker/0:9 Not tainted 5.15.161-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Workqueue: events pwq_unbound_release_workfn Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_address_description+0x63/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x16b/0x1c0 mm/kasan/report.c:451 tcp_probe_timer net/ipv4/tcp_timer.c:384 [inline] tcp_write_timer_handler+0x882/0x9c0 net/ipv4/tcp_timer.c:648 tcp_write_timer+0x12e/0x280 net/ipv4/tcp_timer.c:664 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:synchronize_rcu+0x0/0x1a0 kernel/rcu/tree.c:3790 Code: e8 35 e7 5e 00 e9 68 fd ff ff 48 c7 c7 a0 47 92 8c 48 89 de e8 61 4e bf 02 e9 b5 fa ff ff e8 57 fb b2 08 0f 1f 80 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 54 53 48 83 e4 e0 48 81 ec 00 01 00 00 RSP: 0018:ffffc90002d47b38 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff920005a8f70 RCX: ffffffff913f0f03 RDX: 0000000000000000 RSI: ffffffff8a8b3800 RDI: ffffffff8ad8f740 RBP: ffffc90002d47c08 R08: dffffc0000000000 R09: fffffbfff22c5241 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff913e4788 R13: 1ffff920005a8f6c R14: 0000000000000206 R15: ffffc90002d47b80 lockdep_unregister_key+0x4e6/0x5b0 kernel/locking/lockdep.c:6319 wq_unregister_lockdep kernel/workqueue.c:3518 [inline] pwq_unbound_release_workfn+0x23d/0x290 kernel/workqueue.c:3756 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 Allocated by task 10278: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x53/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233 kmem_cache_zalloc include/linux/slab.h:711 [inline] net_alloc net/core/net_namespace.c:408 [inline] copy_net_ns+0x140/0x5d0 net/core/net_namespace.c:463 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:3101 __do_sys_unshare kernel/fork.c:3175 [inline] __se_sys_unshare kernel/fork.c:3173 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3173 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 144: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kmem_cache_free+0x91/0x1f0 mm/slub.c:3515 net_free net/core/net_namespace.c:437 [inline] cleanup_net+0xab5/0xb60 net/core/net_namespace.c:620 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 The buggy address belongs to the object at ffff888078ba3500 which belongs to the cache net_namespace of size 6528 The buggy address is located 1677 bytes inside of 6528-byte region [ffff888078ba3500, ffff888078ba4e80) The buggy address belongs to the page: page:ffffea0001e2e800 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888078ba0000 pfn:0x78ba0 head:ffffea0001e2e800 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 0000000100000001 ffff888011dec3c0 raw: ffff888078ba0000 0000000080040003 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3511, ts 56403951815, free_ts 56390889629 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xbb/0x4b0 mm/slub.c:1975 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc+0x18e/0x280 mm/slub.c:3233 kmem_cache_zalloc include/linux/slab.h:711 [inline] net_alloc net/core/net_namespace.c:408 [inline] copy_net_ns+0x140/0x5d0 net/core/net_namespace.c:463 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:3101 __do_sys_unshare kernel/fork.c:3175 [inline] __se_sys_unshare kernel/fork.c:3173 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3173 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396 free_slab mm/slub.c:2015 [inline] discard_slab mm/slub.c:2021 [inline] __unfreeze_partials+0x1b7/0x210 mm/slub.c:2507 put_cpu_partial+0x132/0x1a0 mm/slub.c:2587 do_slab_free mm/slub.c:3487 [inline] ___cache_free+0xe3/0x100 mm/slub.c:3506 qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x53/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] __kmalloc_node+0x151/0x390 mm/slub.c:4451 kmalloc_node include/linux/slab.h:614 [inline] kvmalloc_node+0x80/0x140 mm/util.c:619 kvmalloc include/linux/mm.h:805 [inline] kvzalloc include/linux/mm.h:813 [inline] proc_sys_call_handler+0x3d0/0x8a0 fs/proc/proc_sysctl.c:570 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0xacf/0xe50 fs/read_write.c:594 ksys_write+0x1a2/0x2c0 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Memory state around the buggy address: ffff888078ba3a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888078ba3b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888078ba3b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888078ba3c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888078ba3c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: e8 35 e7 5e 00 call 0x5ee73a 5: e9 68 fd ff ff jmp 0xfffffd72 a: 48 c7 c7 a0 47 92 8c mov $0xffffffff8c9247a0,%rdi 11: 48 89 de mov %rbx,%rsi 14: e8 61 4e bf 02 call 0x2bf4e7a 19: e9 b5 fa ff ff jmp 0xfffffad3 1e: e8 57 fb b2 08 call 0x8b2fb7a 23: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) * 2a: 55 push %rbp <-- trapping instruction 2b: 48 89 e5 mov %rsp,%rbp 2e: 41 57 push %r15 30: 41 56 push %r14 32: 41 54 push %r12 34: 53 push %rbx 35: 48 83 e4 e0 and $0xffffffffffffffe0,%rsp 39: 48 81 ec 00 01 00 00 sub $0x100,%rsp