================================================================== BUG: KASAN: slab-out-of-bounds in xfrm_policy_inexact_list_reinsert+0x599/0x650 net/xfrm/xfrm_policy.c:855 Read of size 1 at addr ffff8881bc6753d8 by task syz.0.687/2843 CPU: 1 PID: 2843 Comm: syz.0.687 Not tainted 5.4.289-syzkaller-00025-g49530c73f82d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x241 lib/dump_stack.c:118 print_address_description+0x8c/0x600 mm/kasan/report.c:384 __kasan_report+0xf3/0x120 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 xfrm_policy_inexact_list_reinsert+0x599/0x650 net/xfrm/xfrm_policy.c:855 xfrm_policy_inexact_node_merge net/xfrm/xfrm_policy.c:987 [inline] xfrm_policy_inexact_insert_node+0x8f3/0xb00 net/xfrm/xfrm_policy.c:1043 xfrm_policy_inexact_alloc_chain+0x4f9/0xb10 net/xfrm/xfrm_policy.c:1159 xfrm_policy_inexact_insert+0x69/0x10e0 net/xfrm/xfrm_policy.c:1202 xfrm_policy_insert+0xe1/0x8a0 net/xfrm/xfrm_policy.c:1585 xfrm_add_policy+0x4f2/0x980 net/xfrm/xfrm_user.c:1720 xfrm_user_rcv_msg+0x689/0x9b0 net/xfrm/xfrm_user.c:2775 netlink_rcv_skb+0x1d5/0x420 net/netlink/af_netlink.c:2467 xfrm_netlink_rcv+0x6e/0x80 net/xfrm/xfrm_user.c:2797 netlink_unicast_kernel net/netlink/af_netlink.c:1306 [inline] netlink_unicast+0x936/0xb20 net/netlink/af_netlink.c:1332 netlink_sendmsg+0xa18/0xcf0 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:638 [inline] __sock_sendmsg net/socket.c:650 [inline] ____sys_sendmsg+0x5ac/0x8f0 net/socket.c:2306 ___sys_sendmsg net/socket.c:2360 [inline] __sys_sendmsg+0x28b/0x380 net/socket.c:2406 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7ff19114eda9 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:00007ff18f7b9038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ff191367fa0 RCX: 00007ff19114eda9 RDX: 0000000000004000 RSI: 0000000020000580 RDI: 0000000000000005 RBP: 00007ff1911d02a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff191367fa0 R15: 00007ffc67ba9d18 Allocated by task 2843: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529 kmalloc include/linux/slab.h:561 [inline] sk_prot_alloc+0xbd/0x3e0 net/core/sock.c:1622 sk_alloc+0x35/0x2f0 net/core/sock.c:1680 pfkey_create+0x122/0x670 net/key/af_key.c:154 __sock_create+0x3cb/0x7a0 net/socket.c:1427 sock_create net/socket.c:1478 [inline] __sys_socket+0x132/0x370 net/socket.c:1520 __do_sys_socket net/socket.c:1529 [inline] __se_sys_socket net/socket.c:1527 [inline] __x64_sys_socket+0x76/0x80 net/socket.c:1527 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8881bc675000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 984 bytes inside of 1024-byte region [ffff8881bc675000, ffff8881bc675400) The buggy address belongs to the page: page:ffffea0006f19c00 refcount:1 mapcount:0 mapping:ffff8881f5c02280 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5c02280 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 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) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x18f/0x370 mm/page_alloc.c:2171 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893 alloc_slab_page+0x39/0x3c0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x97/0x440 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x2fe/0x490 mm/slub.c:2667 __slab_alloc+0x62/0xa0 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] __kmalloc_track_caller+0x16d/0x2b0 mm/slub.c:4449 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0xb4/0x4d0 net/core/skbuff.c:210 alloc_skb_fclone include/linux/skbuff.h:1130 [inline] sk_stream_alloc_skb+0x1f4/0xa70 net/ipv4/tcp.c:891 tcp_sendmsg_locked+0xe07/0x3810 net/ipv4/tcp.c:1300 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1450 sock_sendmsg_nosec net/socket.c:638 [inline] __sock_sendmsg net/socket.c:650 [inline] sock_write_iter+0x344/0x470 net/socket.c:1009 call_write_iter include/linux/fs.h:1991 [inline] new_sync_write fs/read_write.c:483 [inline] __vfs_write+0x5d3/0x750 fs/read_write.c:496 vfs_write+0x206/0x4e0 fs/read_write.c:558 ksys_write+0x199/0x2c0 fs/read_write.c:611 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1176 [inline] free_pcp_prepare mm/page_alloc.c:1233 [inline] free_unref_page_prepare+0x297/0x380 mm/page_alloc.c:3085 free_unref_page_list+0x10a/0x590 mm/page_alloc.c:3154 release_pages+0xad8/0xb20 mm/swap.c:842 __pagevec_release+0xc3/0x150 mm/swap.c:862 pagevec_release include/linux/pagevec.h:88 [inline] shmem_undo_range+0x8a5/0x1ad0 mm/shmem.c:875 shmem_truncate_range mm/shmem.c:997 [inline] shmem_evict_inode+0x218/0x9a0 mm/shmem.c:1097 evict+0x4ea/0x960 fs/inode.c:610 __dentry_kill+0x429/0x630 fs/dcache.c:583 dentry_kill+0xb8/0x280 fs/dcache.c:677 dput+0x3c/0x80 fs/dcache.c:864 __fput+0x443/0x680 fs/file_table.c:294 task_work_run+0x140/0x170 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xcaf/0x2bc0 kernel/exit.c:861 do_group_exit+0x138/0x300 kernel/exit.c:984 get_signal+0xdb1/0x1440 kernel/signal.c:2738 do_signal+0xb0/0x11f0 arch/x86/kernel/signal.c:809 Memory state around the buggy address: ffff8881bc675280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881bc675300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881bc675380: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ^ ffff8881bc675400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881bc675480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================