================================================================== 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 ffff8880753d068d by task syz-executor.1/7242 CPU: 0 PID: 7242 Comm: syz-executor.1 Not tainted 5.15.153-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb 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:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1737 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1750 __do_softirq+0x3b3/0x93a kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 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:lock_is_held_type+0x137/0x180 Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f RSP: 0018:ffffc90003817198 EFLAGS: 00000206 RAX: 84f1eb9129953d00 RBX: 0000000000000002 RCX: ffff888023473b80 RDX: 0000000000000000 RSI: ffffffff8a8b27a0 RDI: ffffffff8ad88fc0 RBP: 0000000000000000 R08: ffffffff81a940ac R09: fffff940002d06b7 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246 R13: ffff888023473b80 R14: 00000000ffffffff R15: ffffffff8c91f780 lock_is_held include/linux/lockdep.h:287 [inline] ___might_sleep+0xa2/0x6a0 kernel/sched/core.c:9592 generic_perform_write+0x3e9/0x5b0 mm/filemap.c:3803 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 ext4_file_write_iter+0x87c/0x1990 do_iter_readv_writev+0x594/0x7a0 do_iter_write+0x1ea/0x760 fs/read_write.c:855 iter_file_splice_write+0x806/0xfa0 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0xe3/0x1c0 fs/splice.c:936 splice_direct_to_actor+0x500/0xc10 fs/splice.c:891 do_splice_direct+0x285/0x3d0 fs/splice.c:979 do_sendfile+0x625/0xff0 fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64+0x178/0x1e0 fs/read_write.c:1303 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fe8168dada9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe814e5b0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fe816a08f80 RCX: 00007fe8168dada9 RDX: 0000000000000000 RSI: 000000000000000a RDI: 0000000000000005 RBP: 00007fe81692747a R08: 0000000000000000 R09: 0000000000000000 R10: 0001000000201005 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fe816a08f80 R15: 00007ffe0f968548 Allocated by task 3516: 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:405 [inline] copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:460 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+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb The buggy address belongs to the object at ffff8880753d0000 which belongs to the cache net_namespace of size 6464 The buggy address is located 1677 bytes inside of 6464-byte region [ffff8880753d0000, ffff8880753d1940) The buggy address belongs to the page: page:ffffea0001d4f400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880753d0000 pfn:0x753d0 head:ffffea0001d4f400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 0000000100000001 ffff888011dea3c0 raw: ffff8880753d0000 0000000080040002 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 3516, ts 60182573804, free_ts 60178590077 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:5421 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:405 [inline] copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:460 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+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb 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] slab_alloc mm/slub.c:3228 [inline] __kmalloc_track_caller+0x11e/0x300 mm/slub.c:4925 kvasprintf+0xd6/0x180 lib/kasprintf.c:25 kobject_set_name_vargs+0x5d/0x110 lib/kobject.c:297 kobject_add_varg lib/kobject.c:392 [inline] kobject_init_and_add+0xda/0x190 lib/kobject.c:481 netdev_queue_add_kobject net/core/net-sysfs.c:1666 [inline] netdev_queue_update_kobjects+0x186/0x3f0 net/core/net-sysfs.c:1711 register_queue_kobjects net/core/net-sysfs.c:1772 [inline] netdev_register_kobject+0x263/0x310 net/core/net-sysfs.c:2018 register_netdevice+0x108c/0x1720 net/core/dev.c:10357 Memory state around the buggy address: ffff8880753d0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880753d0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880753d0680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880753d0700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880753d0780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 75 40 jne 0x42 2: 48 c7 04 24 00 00 00 movq $0x0,(%rsp) 9: 00 a: 9c pushf b: 8f 04 24 pop (%rsp) e: f7 04 24 00 02 00 00 testl $0x200,(%rsp) 15: 75 46 jne 0x5d 17: 41 f7 c4 00 02 00 00 test $0x200,%r12d 1e: 74 01 je 0x21 20: fb sti 21: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax 28: 00 00 * 2a: 48 3b 44 24 08 cmp 0x8(%rsp),%rax <-- trapping instruction 2f: 75 3c jne 0x6d 31: 89 e8 mov %ebp,%eax 33: 48 83 c4 10 add $0x10,%rsp 37: 5b pop %rbx 38: 41 5c pop %r12 3a: 41 5d pop %r13 3c: 41 5e pop %r14 3e: 41 5f pop %r15