================================================================== BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0x99c/0x9f0 net/ipv4/tcp_timer.c:594 Read of size 1 at addr ffff88802b1b8745 by task ksoftirqd/1/21 CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 6.1.0-rc5-syzkaller-00326-g77c51ba552a1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15e/0x45d mm/kasan/report.c:395 kasan_report+0xbf/0x1f0 mm/kasan/report.c:495 tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline] tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline] tcp_write_timer_handler+0x99c/0x9f0 net/ipv4/tcp_timer.c:594 tcp_write_timer+0xa6/0x2b0 net/ipv4/tcp_timer.c:637 call_timer_fn+0x1da/0x7c0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers.part.0+0x6a2/0xaf0 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0xb7/0x1d0 kernel/time/timer.c:1803 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x659/0xa20 kernel/smpboot.c:164 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Allocated by task 3661: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x82/0x90 mm/kasan/common.c:325 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:737 [inline] 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+0x2b4/0x3d0 mm/slub.c:3422 kmem_cache_zalloc include/linux/slab.h:679 [inline] net_alloc net/core/net_namespace.c:410 [inline] copy_net_ns+0x129/0x760 net/core/net_namespace.c:465 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc5/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x449/0x920 kernel/fork.c:3188 __do_sys_unshare kernel/fork.c:3259 [inline] __se_sys_unshare kernel/fork.c:3257 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3257 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 insert_work+0x48/0x350 kernel/workqueue.c:1358 __queue_work+0x693/0x13b0 kernel/workqueue.c:1517 call_timer_fn+0x1da/0x7c0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1514 [inline] __run_timers.part.0+0x4a3/0xaf0 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0x156/0x1d0 kernel/time/timer.c:1805 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 Second to last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 insert_work+0x48/0x350 kernel/workqueue.c:1358 __queue_work+0x693/0x13b0 kernel/workqueue.c:1517 call_timer_fn+0x1da/0x7c0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1514 [inline] __run_timers.part.0+0x4a3/0xaf0 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0x156/0x1d0 kernel/time/timer.c:1805 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 The buggy address belongs to the object at ffff88802b1b8000 which belongs to the cache net_namespace of size 6976 The buggy address is located 1861 bytes inside of 6976-byte region [ffff88802b1b8000, ffff88802b1b9b40) The buggy address belongs to the physical page: page:ffffea0000ac6e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802b1b8000 pfn:0x2b1b8 head:ffffea0000ac6e00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff888020d36501 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0000b1e808 ffffea0000886e08 ffff8880121e1500 raw: ffff88802b1b8000 0000000000040002 00000001ffffffff ffff888020d36501 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 3661, tgid 3661 (syz-executor.0), ts 151379868713, free_ts 0 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4288 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5555 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2285 alloc_slab_page mm/slub.c:1794 [inline] allocate_slab+0x213/0x300 mm/slub.c:1939 new_slab mm/slub.c:1992 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3180 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3279 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+0x31a/0x3d0 mm/slub.c:3422 kmem_cache_zalloc include/linux/slab.h:679 [inline] net_alloc net/core/net_namespace.c:410 [inline] copy_net_ns+0x129/0x760 net/core/net_namespace.c:465 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc5/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x449/0x920 kernel/fork.c:3188 __do_sys_unshare kernel/fork.c:3259 [inline] __se_sys_unshare kernel/fork.c:3257 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3257 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page_owner free stack trace missing Memory state around the buggy address: ffff88802b1b8600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802b1b8680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802b1b8700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802b1b8780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802b1b8800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================