================================================================== BUG: KASAN: slab-out-of-bounds in dns_resolver_preparse+0xc9f/0xd60 net/dns_resolver/dns_key.c:127 Read of size 1 at addr ffff88802a472464 by task syz-executor.0/7118 CPU: 1 PID: 7118 Comm: syz-executor.0 Not tainted 6.7.0-rc6-next-20231219-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 dns_resolver_preparse+0xc9f/0xd60 net/dns_resolver/dns_key.c:127 __key_create_or_update+0x453/0xdf0 security/keys/key.c:842 key_create_or_update+0x42/0x50 security/keys/key.c:1007 __do_sys_add_key+0x29c/0x450 security/keys/keyctl.c:134 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x62/0x6a RIP: 0033:0x7f2c5487cbe9 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:00007f2c555100c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8 RAX: ffffffffffffffda RBX: 00007f2c5499bf80 RCX: 00007f2c5487cbe9 RDX: 0000000020000080 RSI: 0000000000000000 RDI: 00000000200003c0 RBP: 00007f2c548c847a R08: 0000000005954306 R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f2c5499bf80 R15: 00007ffd0362a7c8 Allocated by task 7118: kasan_save_stack+0x33/0x50 mm/kasan/common.c:47 kasan_set_track+0x24/0x30 mm/kasan/common.c:61 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slub.c:3985 [inline] __kmalloc_node+0x226/0x480 mm/slub.c:3992 kmalloc_node include/linux/slab.h:610 [inline] kvmalloc_node+0x99/0x1a0 mm/util.c:634 kvmalloc include/linux/slab.h:728 [inline] __do_sys_add_key+0x1f8/0x450 security/keys/keyctl.c:116 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x62/0x6a The buggy address belongs to the object at ffff88802a472460 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 0 bytes to the right of allocated 4-byte region [ffff88802a472460, ffff88802a472464) The buggy address belongs to the physical page: page:ffffea0000a91c80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a472 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888013041280 ffffea000169b800 dead000000000002 raw: 0000000000000000 0000000080800080 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5101, tgid 5101 (syz-executor.2), ts 190655416041, free_ts 190582131271 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1540 prep_new_page mm/page_alloc.c:1547 [inline] get_page_from_freelist+0xa19/0x3740 mm/page_alloc.c:3355 __alloc_pages+0x22e/0x2410 mm/page_alloc.c:4611 alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133 alloc_slab_page mm/slub.c:2191 [inline] allocate_slab mm/slub.c:2358 [inline] new_slab+0x283/0x3c0 mm/slub.c:2411 ___slab_alloc+0x4ab/0x1990 mm/slub.c:3544 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3629 __slab_alloc_node mm/slub.c:3682 [inline] slab_alloc_node mm/slub.c:3854 [inline] __do_kmalloc_node mm/slub.c:3984 [inline] __kmalloc_node_track_caller+0x367/0x470 mm/slub.c:4005 kstrdup+0x3c/0x70 mm/util.c:62 kstrdup_const+0x5f/0x70 mm/util.c:85 __kernfs_new_node+0x9c/0x890 fs/kernfs/dir.c:611 kernfs_new_node+0x18c/0x240 fs/kernfs/dir.c:691 kernfs_create_dir_ns+0x4c/0x150 fs/kernfs/dir.c:1052 cgroup_create kernel/cgroup/cgroup.c:5611 [inline] cgroup_mkdir+0x543/0x10f0 kernel/cgroup/cgroup.c:5746 kernfs_iop_mkdir+0x14a/0x1d0 fs/kernfs/dir.c:1237 vfs_mkdir+0x573/0x820 fs/namei.c:4112 page last free pid 5183 tgid 5183 stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x51f/0xb10 mm/page_alloc.c:2390 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2530 __put_partials+0x14c/0x160 mm/slub.c:2926 qlink_free mm/kasan/quarantine.c:178 [inline] qlist_free_all+0xc1/0x1e0 mm/kasan/quarantine.c:194 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:301 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slub.c:3817 [inline] slab_alloc_node mm/slub.c:3864 [inline] kmem_cache_alloc_node+0x177/0x340 mm/slub.c:3907 __alloc_skb+0x287/0x330 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1298 [inline] alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6365 sock_alloc_send_pskb+0x7e1/0x970 net/core/sock.c:2776 sock_alloc_send_skb include/net/sock.h:1884 [inline] mld_newpack.isra.0+0x1ed/0x790 net/ipv6/mcast.c:1746 add_grhead+0x295/0x340 net/ipv6/mcast.c:1849 add_grec+0x111a/0x1670 net/ipv6/mcast.c:1987 mld_send_initial_cr.part.0+0xe2/0x260 net/ipv6/mcast.c:2233 mld_send_initial_cr net/ipv6/mcast.c:2224 [inline] mld_dad_work+0x57/0x2e0 net/ipv6/mcast.c:2259 process_one_work+0x8a4/0x15f0 kernel/workqueue.c:2633 Memory state around the buggy address: ffff88802a472300: fb fc fc fc fb fc fc fc fb fc fc fc fb fc fc fc ffff88802a472380: 05 fc fc fc fb fc fc fc fb fc fc fc fa fc fc fc >ffff88802a472400: fb fc fc fc 00 fc fc fc fa fc fc fc 04 fc fc fc ^ ffff88802a472480: fb fc fc fc 06 fc fc fc 06 fc fc fc 06 fc fc fc ffff88802a472500: 05 fc fc fc 07 fc fc fc 07 fc fc fc 07 fc fc fc 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