================================================================== 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 ffff88807c78bb0d by task syz-executor.1/9063 CPU: 1 PID: 9063 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:__sanitizer_cov_trace_switch+0xb/0xe0 kernel/kcov.c:303 Code: 00 00 48 89 7c 11 10 48 89 74 11 18 4c 89 44 11 20 49 ff c2 4c 89 12 c3 0f 1f 80 00 00 00 00 41 57 41 56 41 54 53 48 8b 46 08 <48> 83 c0 f8 48 c1 c0 3d 48 83 f8 07 0f 87 ac 00 00 00 b9 8b 00 00 RSP: 0018:ffffc900031c7bb0 EFLAGS: 00000287 RAX: 0000000000000008 RBX: 0000000000000003 RCX: 0000000000040000 RDX: ffffc900049fa000 RSI: ffffffff8ce9e7a0 RDI: 0000000000000003 RBP: 0000000000000040 R08: ffffffff83c4bb96 R09: ffffc900031c7c80 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff92000638fa0 R14: 0000000000004c00 R15: ffffc900031c7c80 tomoyo_print_ulong+0x23/0xa0 security/tomoyo/util.c:229 tomoyo_audit_path_number_log security/tomoyo/file.c:233 [inline] tomoyo_path_number_perm+0x4e0/0x810 security/tomoyo/file.c:734 security_file_ioctl+0x6d/0xa0 security/security.c:1555 __do_sys_ioctl fs/ioctl.c:868 [inline] __se_sys_ioctl+0x47/0x160 fs/ioctl.c:860 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: 0033:0x7f24e1167b0b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007f24df6e7e50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f24e1167b0b RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000062f R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f24df6e7f80 R14: 00007f24df6e7f40 R15: 00007f24d72c8000 Allocated by task 6237: 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 Freed by task 3810: 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:434 [inline] cleanup_net+0xab5/0xb60 net/core/net_namespace.c:617 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff88807c78b480 which belongs to the cache net_namespace of size 6464 The buggy address is located 1677 bytes inside of 6464-byte region [ffff88807c78b480, ffff88807c78cdc0) The buggy address belongs to the page: page:ffffea0001f1e200 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807c788000 pfn:0x7c788 head:ffffea0001f1e200 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff8880231bd881 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011dea3c0 raw: ffff88807c788000 0000000080040003 00000001ffffffff ffff8880231bd881 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 3786, ts 69401954009, free_ts 69398054437 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 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] kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233 getname_flags+0xb8/0x4e0 fs/namei.c:138 getname fs/namei.c:217 [inline] __do_sys_symlinkat fs/namei.c:4475 [inline] __se_sys_symlinkat fs/namei.c:4472 [inline] __x64_sys_symlinkat+0x78/0xa0 fs/namei.c:4472 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 Memory state around the buggy address: ffff88807c78ba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c78ba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807c78bb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807c78bb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c78bc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 48 89 7c 11 10 mov %rdi,0x10(%rcx,%rdx,1) 7: 48 89 74 11 18 mov %rsi,0x18(%rcx,%rdx,1) c: 4c 89 44 11 20 mov %r8,0x20(%rcx,%rdx,1) 11: 49 ff c2 inc %r10 14: 4c 89 12 mov %r10,(%rdx) 17: c3 ret 18: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 1f: 41 57 push %r15 21: 41 56 push %r14 23: 41 54 push %r12 25: 53 push %rbx 26: 48 8b 46 08 mov 0x8(%rsi),%rax * 2a: 48 83 c0 f8 add $0xfffffffffffffff8,%rax <-- trapping instruction 2e: 48 c1 c0 3d rol $0x3d,%rax 32: 48 83 f8 07 cmp $0x7,%rax 36: 0f 87 ac 00 00 00 ja 0xe8 3c: b9 .byte 0xb9 3d: 8b 00 mov (%rax),%eax