netlink: 24 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 'syz-executor.2': attribute type 8 has an invalid length. ================================================================== BUG: KASAN: stack-out-of-bounds in __nla_validate_parse+0x136/0x2bd0 lib/nlattr.c:588 Write of size 32 at addr ffffc90015dc6e20 by task syz-executor.2/13729 CPU: 1 PID: 13729 Comm: syz-executor.2 Not tainted 6.5.0-rc2-syzkaller-00307-gd192f5382581 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x175/0x1b0 mm/kasan/report.c:588 kasan_check_range+0x27e/0x290 mm/kasan/generic.c:187 __asan_memset+0x23/0x40 mm/kasan/shadow.c:84 __nla_validate_parse+0x136/0x2bd0 lib/nlattr.c:588 __nla_parse+0x40/0x50 lib/nlattr.c:700 nla_parse_nested include/net/netlink.h:1262 [inline] fl_set_key_cfm+0x1e3/0x440 net/sched/cls_flower.c:1718 fl_set_key+0x2168/0x6620 net/sched/cls_flower.c:1884 fl_tmplt_create+0x1fe/0x510 net/sched/cls_flower.c:2666 tc_chain_tmplt_add net/sched/cls_api.c:2959 [inline] tc_ctl_chain+0x131d/0x1ac0 net/sched/cls_api.c:3068 rtnetlink_rcv_msg+0x82b/0xf50 net/core/rtnetlink.c:6424 netlink_rcv_skb+0x1df/0x430 net/netlink/af_netlink.c:2549 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x7c3/0x990 net/netlink/af_netlink.c:1365 netlink_sendmsg+0xa2a/0xd60 net/netlink/af_netlink.c:1914 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg net/socket.c:748 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2494 ___sys_sendmsg net/socket.c:2548 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2577 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f92ef07cb29 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f92efdac0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f92ef19bf80 RCX: 00007f92ef07cb29 RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000004 RBP: 00007f92ef0c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f92ef19bf80 R15: 00007ffcd3c0bfe8 The buggy address belongs to stack of task syz-executor.2/13729 and is located at offset 32 in frame: fl_set_key_cfm+0x0/0x440 net/sched/cls_flower.c:374 This frame has 1 object: [32, 56) 'nla_cfm_opt' The buggy address belongs to the virtual mapping at [ffffc90015dc0000, ffffc90015dc9000) created by: copy_process+0x5c8/0x4290 kernel/fork.c:2330 The buggy address belongs to the physical page: page:ffffea0000aa7b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a9ec memcg:ffff88802434fd82 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff ffff88802434fd82 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 13724, tgid 13724 (syz-executor.2), ts 2021079172293, free_ts 2017286577856 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1570 prep_new_page mm/page_alloc.c:1577 [inline] get_page_from_freelist+0x31e8/0x3370 mm/page_alloc.c:3221 __alloc_pages+0x255/0x670 mm/page_alloc.c:4477 vm_area_alloc_pages mm/vmalloc.c:3059 [inline] __vmalloc_area_node mm/vmalloc.c:3135 [inline] __vmalloc_node_range+0x9a3/0x1490 mm/vmalloc.c:3316 alloc_thread_stack_node kernel/fork.c:309 [inline] dup_task_struct+0x3e5/0x7d0 kernel/fork.c:1113 copy_process+0x5c8/0x4290 kernel/fork.c:2330 kernel_clone+0x222/0x800 kernel/fork.c:2912 __do_sys_clone3 kernel/fork.c:3213 [inline] __se_sys_clone3+0x2cb/0x340 kernel/fork.c:3197 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 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:1161 [inline] free_unref_page_prepare+0x903/0xa30 mm/page_alloc.c:2348 free_unref_page_list+0x596/0x830 mm/page_alloc.c:2489 release_pages+0x2193/0x2470 mm/swap.c:1042 __folio_batch_release+0x84/0x100 mm/swap.c:1062 folio_batch_release include/linux/pagevec.h:83 [inline] mapping_try_invalidate+0x515/0x640 mm/truncate.c:536 xfs_free_buftarg+0x7d/0xd0 fs/xfs/xfs_buf.c:1947 xfs_fs_put_super+0x252/0x2d0 fs/xfs/xfs_super.c:1150 generic_shutdown_super+0x134/0x340 fs/super.c:499 kill_block_super+0x68/0xa0 fs/super.c:1417 deactivate_locked_super+0xa4/0x110 fs/super.c:330 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1254 task_work_run+0x24a/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 Memory state around the buggy address: ffffc90015dc6d00: 00 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90015dc6d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc90015dc6e00: f1 f1 f1 f1 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 ^ ffffc90015dc6e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90015dc6f00: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3 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