================================================================== BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:388 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0x7ef/0x930 net/ipv4/tcp_timer.c:652 Read of size 1 at addr ffff888079d75c05 by task syz-executor.2/11919 CPU: 0 PID: 11919 Comm: syz-executor.2 Not tainted 6.1.82-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 mm/kasan/report.c:284 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:395 kasan_report+0x136/0x160 mm/kasan/report.c:495 tcp_probe_timer net/ipv4/tcp_timer.c:388 [inline] tcp_write_timer_handler+0x7ef/0x930 net/ipv4/tcp_timer.c:652 tcp_write_timer+0x12e/0x280 net/ipv4/tcp_timer.c:665 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1790 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 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 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:169 [inline] RIP: 0010:unwind_next_frame+0x208/0x2220 arch/x86/kernel/unwind_orc.c:448 Code: 80 e0 85 8f 48 89 d8 48 c1 e8 03 0f b6 04 38 84 c0 0f 85 d0 1a 00 00 44 8b 23 44 89 f0 ff c0 48 8d 1c 85 80 e0 85 8f 48 89 d8 <48> c1 e8 03 0f b6 04 38 84 c0 0f 85 d0 1a 00 00 44 8b 03 41 ff c0 RSP: 0018:ffffc9000a66f4e0 EFLAGS: 00000206 RAX: ffffffff8f8967d0 RBX: ffffffff8f8967d0 RCX: 000000000009c07f RDX: dffffc0000000000 RSI: ffffffff81e1d347 RDI: dffffc0000000000 RBP: 1ffff920014cdebe R08: 0000000000000001 R09: ffffc9000a66f6b0 R10: 0000000000000000 R11: dffffc0000000001 R12: 000000000002b111 R13: ffffffff81e1d346 R14: 000000000000e1d3 R15: 000000000009c07f arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:955 [inline] __kmalloc+0xb2/0x230 mm/slab_common.c:968 kmalloc include/linux/slab.h:561 [inline] tomoyo_realpath_from_path+0xcb/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x29f/0x710 security/tomoyo/file.c:822 tomoyo_path_unlink+0xcc/0x100 security/tomoyo/tomoyo.c:149 security_path_unlink+0xd7/0x130 security/security.c:1189 do_unlinkat+0x3e0/0x820 fs/namei.c:4388 __do_sys_unlink fs/namei.c:4440 [inline] __se_sys_unlink fs/namei.c:4438 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4438 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f303287d557 Code: 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 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:00007ffcd23a05f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f303287d557 RDX: 00007ffcd23a0620 RSI: 00007ffcd23a06b0 RDI: 00007ffcd23a06b0 RBP: 00007ffcd23a06b0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffcd23a1770 R13: 00007f30328c93b9 R14: 00000000000bc989 R15: 0000000000000009 Allocated by task 8173: 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:682 [inline] net_alloc net/core/net_namespace.c:410 [inline] copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:465 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+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd 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:1474 expire_timers kernel/time/timer.c:1514 [inline] __run_timers+0x6a8/0x890 kernel/time/timer.c:1790 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 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:1474 expire_timers kernel/time/timer.c:1514 [inline] __run_timers+0x6a8/0x890 kernel/time/timer.c:1790 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 The buggy address belongs to the object at ffff888079d754c0 which belongs to the cache net_namespace of size 6976 The buggy address is located 1861 bytes inside of 6976-byte region [ffff888079d754c0, ffff888079d77000) The buggy address belongs to the physical page: page:ffffea0001e75c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888079d73880 pfn:0x79d70 head:ffffea0001e75c00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88807be9b7c1 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888012626500 raw: ffff888079d73880 0000000080040003 00000001ffffffff ffff88807be9b7c1 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 3568, tgid 3568 (syz-executor.4), ts 80502908015, free_ts 71281093360 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2513 prep_new_page mm/page_alloc.c:2520 [inline] get_page_from_freelist+0x31a1/0x3320 mm/page_alloc.c:4279 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5545 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:682 [inline] net_alloc net/core/net_namespace.c:410 [inline] copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:465 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+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1440 [inline] free_pcp_prepare mm/page_alloc.c:1490 [inline] free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3358 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3453 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 mt_alloc_one lib/maple_tree.c:152 [inline] mas_alloc_nodes+0x276/0x800 lib/maple_tree.c:1277 mas_node_count_gfp lib/maple_tree.c:1359 [inline] mas_preallocate+0x12d/0x350 lib/maple_tree.c:5805 vma_expand+0x271/0x8f0 mm/mmap.c:544 mmap_region+0xc3f/0x1fa0 mm/mmap.c:2730 do_mmap+0x8c5/0xf60 mm/mmap.c:1425 vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:520 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888079d75b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888079d75b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888079d75c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888079d75c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888079d75d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 85 8f 48 89 d8 48 test %ecx,0x48d88948(%rdi) 6: c1 e8 03 shr $0x3,%eax 9: 0f b6 04 38 movzbl (%rax,%rdi,1),%eax d: 84 c0 test %al,%al f: 0f 85 d0 1a 00 00 jne 0x1ae5 15: 44 8b 23 mov (%rbx),%r12d 18: 44 89 f0 mov %r14d,%eax 1b: ff c0 inc %eax 1d: 48 8d 1c 85 80 e0 85 lea -0x707a1f80(,%rax,4),%rbx 24: 8f 25: 48 89 d8 mov %rbx,%rax * 28: 48 c1 e8 03 shr $0x3,%rax <-- trapping instruction 2c: 0f b6 04 38 movzbl (%rax,%rdi,1),%eax 30: 84 c0 test %al,%al 32: 0f 85 d0 1a 00 00 jne 0x1b08 38: 44 8b 03 mov (%rbx),%r8d 3b: 41 ff c0 inc %r8d