================================================================== 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 ffff8880294400a4 by task syz-executor.3/14729 CPU: 0 PID: 14729 Comm: syz-executor.3 Not tainted 6.7.0-rc5-next-20231214-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 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: 0033:0x7f0a7087cba9 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:00007f0a716120c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8 RAX: ffffffffffffffda RBX: 00007f0a7099bf80 RCX: 00007f0a7087cba9 RDX: 0000000020000080 RSI: 0000000000000000 RDI: 00000000200003c0 RBP: 00007f0a708c847a R08: 000000003a2186e8 R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f0a7099bf80 R15: 00007ffcb449a898 Allocated by task 14729: 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:617 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 ffff8880294400a0 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 [ffff8880294400a0, ffff8880294400a4) The buggy address belongs to the physical page: page:ffffea0000a51000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29440 anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888013041280 0000000000000000 dead000000000001 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 0x112820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 23, tgid 23 (kworker/1:0), ts 214598474224, free_ts 214479144983 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+0x3b4/0x440 mm/slub.c:3998 kmalloc_array include/linux/slab.h:627 [inline] kcalloc include/linux/slab.h:658 [inline] nsim_fib6_event_init drivers/net/netdevsim/fib.c:810 [inline] nsim_fib6_prepare_event drivers/net/netdevsim/fib.c:947 [inline] nsim_fib_event_schedule_work drivers/net/netdevsim/fib.c:1003 [inline] nsim_fib_event_nb+0x444/0xec0 drivers/net/netdevsim/fib.c:1043 notifier_call_chain+0xb6/0x3d0 kernel/notifier.c:93 atomic_notifier_call_chain+0x71/0x1b0 kernel/notifier.c:231 call_fib_notifiers+0x33/0x70 net/core/fib_notifier.c:35 call_fib6_entry_notifiers net/ipv6/ip6_fib.c:404 [inline] fib6_add_rt2node net/ipv6/ip6_fib.c:1229 [inline] fib6_add+0x25ce/0x47d0 net/ipv6/ip6_fib.c:1483 __ip6_ins_rt net/ipv6/route.c:1303 [inline] ip6_ins_rt+0xb6/0x110 net/ipv6/route.c:1313 __ipv6_ifa_notify+0xcb1/0x10a0 net/ipv6/addrconf.c:6213 ipv6_ifa_notify net/ipv6/addrconf.c:6252 [inline] addrconf_dad_completed+0x19d/0x1030 net/ipv6/addrconf.c:4263 page last free pid 5101 tgid 5101 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+0x136/0x320 mm/slub.c:3871 getname_flags.part.0+0x50/0x4e0 fs/namei.c:140 getname_flags include/linux/audit.h:321 [inline] getname fs/namei.c:219 [inline] __do_sys_mkdirat fs/namei.c:4150 [inline] __se_sys_mkdirat fs/namei.c:4148 [inline] __x64_sys_mkdirat+0xff/0x170 fs/namei.c:4148 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 Memory state around the buggy address: ffff88802943ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888029440000: fb fc fc fc fb fc fc fc fb fc fc fc fb fc fc fc >ffff888029440080: fb fc fc fc 04 fc fc fc fb fc fc fc fb fc fc fc ^ ffff888029440100: fb fc fc fc fb fc fc fc fb fc fc fc 06 fc fc fc ffff888029440180: 06 fc fc fc 06 fc fc fc 05 fc fc fc 05 fc fc fc ==================================================================