================================================================== 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 ffff88807875068d by task syz-executor.0/25229 CPU: 1 PID: 25229 Comm: syz-executor.0 Not tainted 5.15.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 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:dnotify_flush+0x0/0x4a0 fs/notify/dnotify/dnotify.c:136 Code: 8d 4c 24 40 80 e1 07 80 c1 03 38 c1 0f 8c 1e fe ff ff 48 8d 7c 24 40 e8 4e e5 e1 ff e9 0f fe ff ff e8 04 b8 33 08 cc cc cc cc <55> 41 57 41 56 41 55 41 54 53 48 83 ec 28 49 89 f5 49 89 ff 48 bb RSP: 0018:ffffc90003497ed0 EFLAGS: 00000293 RAX: ffffffff81d488b0 RBX: 00000000000d801e RCX: ffff888030fbd940 RDX: 0000000000000000 RSI: ffff8880235ded00 RDI: ffff88807f1a7900 RBP: 0000000000000000 R08: ffffffff81d488a7 R09: ffffed100fe34f30 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88807f1a7900 R13: dffffc0000000000 R14: ffff8880235ded00 R15: 0000000000000000 filp_close+0xfb/0x150 fs/open.c:1322 __do_sys_close fs/open.c:1338 [inline] __se_sys_close fs/open.c:1336 [inline] __x64_sys_close+0x36/0x80 fs/open.c:1336 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: 0033:0x7f7f6ee99c9a Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24 RSP: 002b:00007fff8e764fe0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f7f6ee99c9a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f7f6eee7502 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000004 R13: 00007fff8e765020 R14: 0000000000000001 R15: 0000000000000001 Allocated by task 22604: 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 22768: 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 ffff888078750000 which belongs to the cache net_namespace of size 6464 The buggy address is located 1677 bytes inside of 6464-byte region [ffff888078750000, ffff888078751940) The buggy address belongs to the page: page:ffffea0001e1d400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x78750 head:ffffea0001e1d400 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff8880234bc8c1 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011dea3c0 raw: 0000000000000000 0000000080040004 00000001ffffffff ffff8880234bc8c1 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 22225, ts 609692849110, free_ts 609682909002 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 copy_namespaces+0x365/0x3b0 kernel/nsproxy.c:178 copy_process+0x1841/0x3ef0 kernel/fork.c:2209 kernel_clone+0x210/0x960 kernel/fork.c:2604 __do_sys_clone kernel/fork.c:2721 [inline] __se_sys_clone kernel/fork.c:2705 [inline] __x64_sys_clone+0x23f/0x290 kernel/fork.c:2705 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+0x120/0x300 mm/slub.c:4403 kmalloc include/linux/slab.h:596 [inline] tomoyo_realpath_from_path+0xd8/0x5e0 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x273/0x6b0 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x120 security/security.c:1348 vfs_getattr+0x26/0x360 fs/stat.c:157 vfs_statx+0x18f/0x3b0 fs/stat.c:225 vfs_fstatat fs/stat.c:243 [inline] __do_sys_newfstatat fs/stat.c:411 [inline] __se_sys_newfstatat fs/stat.c:405 [inline] __x64_sys_newfstatat+0x12c/0x1b0 fs/stat.c:405 Memory state around the buggy address: ffff888078750580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888078750600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888078750680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888078750700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888078750780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 8d 4c 24 40 lea 0x40(%rsp),%ecx 4: 80 e1 07 and $0x7,%cl 7: 80 c1 03 add $0x3,%cl a: 38 c1 cmp %al,%cl c: 0f 8c 1e fe ff ff jl 0xfffffe30 12: 48 8d 7c 24 40 lea 0x40(%rsp),%rdi 17: e8 4e e5 e1 ff call 0xffe1e56a 1c: e9 0f fe ff ff jmp 0xfffffe30 21: e8 04 b8 33 08 call 0x833b82a 26: cc int3 27: cc int3 28: cc int3 29: cc int3 * 2a: 55 push %rbp <-- trapping instruction 2b: 41 57 push %r15 2d: 41 56 push %r14 2f: 41 55 push %r13 31: 41 54 push %r12 33: 53 push %rbx 34: 48 83 ec 28 sub $0x28,%rsp 38: 49 89 f5 mov %rsi,%r13 3b: 49 89 ff mov %rdi,%r15 3e: 48 rex.W 3f: bb .byte 0xbb