================================================================== BUG: KASAN: slab-use-after-free in tcp_can_ingest net/ipv4/tcp_input.c:4896 [inline] BUG: KASAN: slab-use-after-free in tcp_prune_ofo_queue+0x37e/0x6e0 net/ipv4/tcp_input.c:5520 Read of size 4 at addr ffff88805ad6ebd0 by task syz.3.7846/26252 CPU: 1 UID: 0 PID: 26252 Comm: syz.3.7846 Not tainted 6.16.0-rc6-next-20250716-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x230 mm/kasan/report.c:480 kasan_report+0x118/0x150 mm/kasan/report.c:593 tcp_can_ingest net/ipv4/tcp_input.c:4896 [inline] tcp_prune_ofo_queue+0x37e/0x6e0 net/ipv4/tcp_input.c:5520 tcp_prune_queue net/ipv4/tcp_input.c:5575 [inline] tcp_try_rmem_schedule+0xb6b/0x1830 net/ipv4/tcp_input.c:4907 tcp_data_queue+0x4e3/0x6380 net/ipv4/tcp_input.c:5192 tcp_rcv_established+0xf9e/0x1eb0 net/ipv4/tcp_input.c:6208 tcp_v4_do_rcv+0xa23/0xce0 net/ipv4/tcp_ipv4.c:1925 sk_backlog_rcv include/net/sock.h:1148 [inline] __release_sock+0x21c/0x350 net/core/sock.c:3188 release_sock+0x5f/0x1f0 net/core/sock.c:3742 tcp_sendmsg+0x39/0x50 net/ipv4/tcp.c:1394 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x19c/0x270 net/socket.c:729 __sys_sendto+0x3bd/0x520 net/socket.c:2228 __do_sys_sendto net/socket.c:2235 [inline] __se_sys_sendto net/socket.c:2231 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2231 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb4a6d8e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb4a7c0d038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fb4a6fb5fa0 RCX: 00007fb4a6d8e929 RDX: 000000000000059a RSI: 0000200000000580 RDI: 0000000000000003 RBP: 00007fb4a6e10ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000010008095 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb4a6fb5fa0 R15: 00007ffcf1f9bbd8 Allocated by task 26252: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4281 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:659 alloc_skb_fclone include/linux/skbuff.h:1386 [inline] tcp_stream_alloc_skb+0x3d/0x340 net/ipv4/tcp.c:892 tso_fragment net/ipv4/tcp_output.c:2174 [inline] tcp_write_xmit+0xeec/0x67f0 net/ipv4/tcp_output.c:2819 __tcp_push_pending_frames+0x97/0x360 net/ipv4/tcp_output.c:3016 tcp_push_pending_frames include/net/tcp.h:2173 [inline] tcp_data_snd_check net/ipv4/tcp_input.c:5662 [inline] tcp_rcv_established+0x1012/0x1eb0 net/ipv4/tcp_input.c:6210 tcp_v4_do_rcv+0xa23/0xce0 net/ipv4/tcp_ipv4.c:1925 sk_backlog_rcv include/net/sock.h:1148 [inline] __release_sock+0x21c/0x350 net/core/sock.c:3188 release_sock+0x5f/0x1f0 net/core/sock.c:3742 tcp_sendmsg+0x39/0x50 net/ipv4/tcp.c:1394 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x19c/0x270 net/socket.c:729 __sys_sendto+0x3bd/0x520 net/socket.c:2228 __do_sys_sendto net/socket.c:2235 [inline] __se_sys_sendto net/socket.c:2231 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2231 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 26252: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4782 tcp_prune_ofo_queue+0x198/0x6e0 net/ipv4/tcp_input.c:5517 tcp_prune_queue net/ipv4/tcp_input.c:5575 [inline] tcp_try_rmem_schedule+0xb6b/0x1830 net/ipv4/tcp_input.c:4907 tcp_data_queue+0x4e3/0x6380 net/ipv4/tcp_input.c:5192 tcp_rcv_established+0xf9e/0x1eb0 net/ipv4/tcp_input.c:6208 tcp_v4_do_rcv+0xa23/0xce0 net/ipv4/tcp_ipv4.c:1925 sk_backlog_rcv include/net/sock.h:1148 [inline] __release_sock+0x21c/0x350 net/core/sock.c:3188 release_sock+0x5f/0x1f0 net/core/sock.c:3742 tcp_sendmsg+0x39/0x50 net/ipv4/tcp.c:1394 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x19c/0x270 net/socket.c:729 __sys_sendto+0x3bd/0x520 net/socket.c:2228 __do_sys_sendto net/socket.c:2235 [inline] __se_sys_sendto net/socket.c:2231 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2231 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805ad6ea00 which belongs to the cache skbuff_fclone_cache of size 488 The buggy address is located 464 bytes inside of freed 488-byte region [ffff88805ad6ea00, ffff88805ad6ebe8) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5ad6e head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801dee0b40 0000000000000000 dead000000000001 raw: 0000000000000000 00000000800c000c 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801dee0b40 0000000000000000 dead000000000001 head: 0000000000000000 00000000800c000c 00000000f5000000 0000000000000000 head: 00fff00000000001 ffffea00016b5b81 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5834, tgid 5834 (syz-executor), ts 610565850827, free_ts 610565391009 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_node_noprof+0x280/0x3c0 mm/slub.c:4281 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:659 alloc_skb_fclone include/linux/skbuff.h:1386 [inline] tcp_stream_alloc_skb+0x3d/0x340 net/ipv4/tcp.c:892 tcp_sendmsg_locked+0xefc/0x56d0 net/ipv4/tcp.c:1198 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1393 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x19c/0x270 net/socket.c:729 sock_write_iter+0x258/0x330 net/socket.c:1179 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x54b/0xa90 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 page last free pid 21012 tgid 21011 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 pagetable_free include/linux/mm.h:2896 [inline] pagetable_dtor_free+0x2d2/0x3b0 include/linux/mm.h:2994 mm_free_pgd kernel/fork.c:540 [inline] __mmdrop+0xb5/0x460 kernel/fork.c:679 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x648/0x2300 kernel/exit.c:947 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88805ad6ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805ad6eb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805ad6eb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ^ ffff88805ad6ec00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805ad6ec80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================