================================================================== 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+0x6ec/0x808 net/ipv4/tcp_timer.c:652 Read of size 1 at addr ffff0000d5760745 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.84-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x174/0x4c0 mm/kasan/report.c:395 kasan_report+0xd4/0x130 mm/kasan/report.c:495 __asan_report_load1_noabort+0x2c/0x38 mm/kasan/report_generic.c:348 tcp_probe_timer net/ipv4/tcp_timer.c:388 [inline] tcp_write_timer_handler+0x6ec/0x808 net/ipv4/tcp_timer.c:652 tcp_write_timer+0x170/0x2e4 net/ipv4/tcp_timer.c:665 call_timer_fn+0x1c0/0xa1c kernel/time/timer.c:1504 expire_timers kernel/time/timer.c:1549 [inline] __run_timers+0x554/0x718 kernel/time/timer.c:1820 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1833 __do_softirq+0x314/0xe38 kernel/softirq.c:571 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:80 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:893 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:85 invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0x264/0x4d4 kernel/softirq.c:650 irq_exit_rcu+0x14/0x84 kernel/softirq.c:662 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline] el1_interrupt+0x38/0x68 arch/arm64/kernel/entry-common.c:486 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581 arch_local_irq_enable+0xc/0x18 arch/arm64/include/asm/irqflags.h:35 default_idle_call+0x68/0xdc kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1e0/0x514 kernel/sched/idle.c:303 cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:401 rest_init+0x2d8/0x2f0 init/main.c:732 start_kernel+0x0/0x608 init/main.c:892 start_kernel+0x448/0x608 init/main.c:1139 __primary_switched+0xb8/0xc0 arch/arm64/kernel/head.S:468 Allocated by task 10612: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505 __kasan_slab_alloc+0x74/0x8c mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x74/0x458 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+0x230/0x37c 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+0x124/0x590 net/core/net_namespace.c:465 create_new_namespaces+0x344/0x614 kernel/nsproxy.c:110 copy_namespaces+0x354/0x3bc kernel/nsproxy.c:178 copy_process+0x186c/0x38d0 kernel/fork.c:2270 kernel_clone+0x1d8/0x98c kernel/fork.c:2682 __do_sys_clone kernel/fork.c:2823 [inline] __se_sys_clone kernel/fork.c:2791 [inline] __arm64_sys_clone+0x1e0/0x234 kernel/fork.c:2791 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Freed by task 4646: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516 ____kasan_slab_free+0x144/0x1c0 mm/kasan/common.c:236 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] kmem_cache_free+0x2f0/0x588 mm/slub.c:3683 net_free net/core/net_namespace.c:439 [inline] cleanup_net+0x888/0x994 net/core/net_namespace.c:622 process_one_work+0x7ac/0x1404 kernel/workqueue.c:2292 worker_thread+0x8e4/0xfec kernel/workqueue.c:2439 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864 Last potentially related work creation: kasan_save_stack+0x40/0x70 mm/kasan/common.c:45 __kasan_record_aux_stack+0xcc/0xe8 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:496 insert_work+0x64/0x384 kernel/workqueue.c:1361 __queue_work+0xd48/0x136c kernel/workqueue.c:1520 delayed_work_timer_fn+0x74/0x90 kernel/workqueue.c:1646 call_timer_fn+0x1c0/0xa1c kernel/time/timer.c:1504 expire_timers kernel/time/timer.c:1544 [inline] __run_timers+0x584/0x718 kernel/time/timer.c:1820 run_timer_softirq+0xcc/0x114 kernel/time/timer.c:1835 __do_softirq+0x314/0xe38 kernel/softirq.c:571 The buggy address belongs to the object at ffff0000d5760000 which belongs to the cache net_namespace of size 6976 The buggy address is located 1861 bytes inside of 6976-byte region [ffff0000d5760000, ffff0000d5761b40) The buggy address belongs to the physical page: page:00000000e10fef42 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x115760 head:00000000e10fef42 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff0000c9580601 flags: 0x5ffe00000010200(slab|head|node=0|zone=2|lastcpupid=0xfff) raw: 05ffe00000010200 0000000000000000 dead000000000122 ffff0000c03de180 raw: 0000000000000000 0000000080040004 00000001ffffffff ffff0000c9580601 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000d5760600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000d5760680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000d5760700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000d5760780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000d5760800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== TCP: request_sock_TCP: Possible SYN flooding on port 2. 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