syzbot

netlink: 76 bytes leftover after parsing attributes in process `syz.2.17'.
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BUG: KASAN: slab-out-of-bounds in is_tcf_tunnel_set include/net/tc_act/tc_tunnel_key.h:33 [inline]
BUG: KASAN: slab-out-of-bounds in tc_setup_flow_action+0x842/0x3280 net/sched/cls_api.c:3639
Read of size 8 at addr ffff88810f8fefc0 by task syz.2.17/357

CPU: 0 PID: 357 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0xe2/0x130 mm/kasan/report.c:452
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
 is_tcf_tunnel_set include/net/tc_act/tc_tunnel_key.h:33 [inline]
 tc_setup_flow_action+0x842/0x3280 net/sched/cls_api.c:3639
 mall_replace_hw_filter+0x293/0x810 net/sched/cls_matchall.c:100
 mall_change+0x528/0x750 net/sched/cls_matchall.c:236
 tc_new_tfilter+0x13f6/0x1a10 net/sched/cls_api.c:2134
 rtnetlink_rcv_msg+0x800/0xb90 net/core/rtnetlink.c:5601
 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2503
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5628
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x88d/0xb30 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2376
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2430
 __sys_sendmsg net/socket.c:2459 [inline]
 __do_sys_sendmsg net/socket.c:2468 [inline]
 __se_sys_sendmsg net/socket.c:2466 [inline]
 __x64_sys_sendmsg+0x1e2/0x2a0 net/socket.c:2466
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f3ef4f36749
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:00007ffeebda7178 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f3ef518cfa0 RCX: 00007f3ef4f36749
RDX: 0000000020000000 RSI: 0000200000000580 RDI: 0000000000000006
RBP: 00007f3ef4fbaf91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3ef518cfa0 R14: 00007f3ef518cfa0 R15: 0000000000000003

Allocated by task 357:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:430 [inline]
 ____kasan_kmalloc mm/kasan/common.c:509 [inline]
 __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:518
 kasan_kmalloc include/linux/kasan.h:254 [inline]
 __kmalloc+0x1a7/0x330 mm/slub.c:4038
 kmalloc include/linux/slab.h:560 [inline]
 kzalloc include/linux/slab.h:667 [inline]
 tcf_idr_create+0x5f/0x790 net/sched/act_api.c:430
 tcf_idr_create_from_flags+0x61/0x70 net/sched/act_api.c:488
 tcf_gact_init+0x2b4/0x520 net/sched/act_gact.c:102
 tcf_action_init_1+0x3e1/0x670 net/sched/act_api.c:1052
 tcf_action_init+0x1e6/0x700 net/sched/act_api.c:1109
 tcf_exts_validate+0x215/0x510 net/sched/cls_api.c:3086
 mall_set_parms+0x4b/0x410 net/sched/cls_matchall.c:171
 mall_change+0x45c/0x750 net/sched/cls_matchall.c:230
 tc_new_tfilter+0x13f6/0x1a10 net/sched/cls_api.c:2134
 rtnetlink_rcv_msg+0x800/0xb90 net/core/rtnetlink.c:5601
 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2503
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5628
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x88d/0xb30 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2376
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2430
 __sys_sendmsg net/socket.c:2459 [inline]
 __do_sys_sendmsg net/socket.c:2468 [inline]
 __se_sys_sendmsg net/socket.c:2466 [inline]
 __x64_sys_sendmsg+0x1e2/0x2a0 net/socket.c:2466
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff88810f8fef00
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 0 bytes to the right of
 192-byte region [ffff88810f8fef00, ffff88810f8fefc0)
The buggy address belongs to the page:
page:ffffea00043e3f80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10f8fe
flags: 0x4000000000000200(slab)
raw: 4000000000000200 dead000000000100 dead000000000122 ffff888100043380
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 353, ts 22889965849, free_ts 22889549112
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x179/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5370
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1813 [inline]
 new_slab+0x84/0x3f0 mm/slub.c:1874
 new_slab_objects mm/slub.c:2632 [inline]
 ___slab_alloc+0x2a6/0x450 mm/slub.c:2796
 __slab_alloc+0x63/0xa0 mm/slub.c:2836
 slab_alloc_node mm/slub.c:2918 [inline]
 slab_alloc mm/slub.c:2960 [inline]
 kmem_cache_alloc_trace+0x1b3/0x2e0 mm/slub.c:2977
 kmalloc include/linux/slab.h:555 [inline]
 kzalloc include/linux/slab.h:667 [inline]
 kernfs_fop_open+0x343/0xb30 fs/kernfs/file.c:628
 do_dentry_open+0x793/0x1090 fs/open.c:819
 vfs_open+0x73/0x80 fs/open.c:944
 do_open fs/namei.c:3399 [inline]
 path_openat+0x27ad/0x3160 fs/namei.c:3517
 do_filp_open+0x1b3/0x3e0 fs/namei.c:3544
 do_sys_openat2+0x14c/0x6d0 fs/open.c:1219
 do_sys_open fs/open.c:1235 [inline]
 __do_sys_openat fs/open.c:1251 [inline]
 __se_sys_openat fs/open.c:1246 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1246
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 free_pcp_prepare mm/page_alloc.c:1421 [inline]
 free_unref_page_prepare+0x2b7/0x2d0 mm/page_alloc.c:3336
 free_unref_page mm/page_alloc.c:3391 [inline]
 free_the_page mm/page_alloc.c:5429 [inline]
 __free_pages+0x14b/0x380 mm/page_alloc.c:5440
 free_pages+0x82/0x90 mm/page_alloc.c:5451
 selinux_genfs_get_sid+0x20b/0x250 security/selinux/hooks.c:1332
 inode_doinit_with_dentry+0x86d/0xd70 security/selinux/hooks.c:1529
 sb_finish_set_opts+0x6a3/0x7d0 security/selinux/hooks.c:555
 selinux_set_mnt_opts+0x156d/0x1bc0 security/selinux/hooks.c:831
 security_sb_set_mnt_opts+0x71/0xd0 security/security.c:915
 vfs_get_tree+0x14e/0x260 fs/super.c:1597
 do_new_mount+0x25a/0xa20 fs/namespace.c:3006
 path_mount+0x572/0xc80 fs/namespace.c:3336
 do_mount fs/namespace.c:3349 [inline]
 __do_sys_mount fs/namespace.c:3557 [inline]
 __se_sys_mount+0x318/0x380 fs/namespace.c:3534
 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3534
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Memory state around the buggy address:
 ffff88810f8fee80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88810f8fef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88810f8fef80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
                                           ^
 ffff88810f8ff000: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88810f8ff080: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
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