================================================================== BUG: KASAN: slab-out-of-bounds in dns_resolver_preparse+0xca9/0xd70 net/dns_resolver/dns_key.c:127 Read of size 1 at addr ffff88807cf54964 by task syz-executor.2/32353 CPU: 1 PID: 32353 Comm: syz-executor.2 Not tainted 6.7.0-rc6-syzkaller-00303-g3f82f1c3a036 #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:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 dns_resolver_preparse+0xca9/0xd70 net/dns_resolver/dns_key.c:127 __key_create_or_update+0x454/0xe00 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_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x62/0xe0 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x70/0x7a RIP: 0023:0xf7fab579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7fa65ac EFLAGS: 00000292 ORIG_RAX: 000000000000011e RAX: ffffffffffffffda RBX: 00000000200003c0 RCX: 0000000000000000 RDX: 0000000020000080 RSI: 0000000000000004 RDI: 000000000f266ba9 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 32353: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc_node+0x5c/0x90 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] kvmalloc_node+0x99/0x1a0 mm/util.c:617 kvmalloc include/linux/slab.h:738 [inline] __do_sys_add_key+0x1f8/0x450 security/keys/keyctl.c:116 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x62/0xe0 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x70/0x7a The buggy address belongs to the object at ffff88807cf54960 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 [ffff88807cf54960, ffff88807cf54964) The buggy address belongs to the physical page: page:ffffea0001f3d500 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7cf54 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888013041280 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080660066 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 5127, tgid 5127 (syz-executor.0), ts 694166200501, free_ts 694165169073 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0xa25/0x36d0 mm/page_alloc.c:3312 __alloc_pages+0x22e/0x2420 mm/page_alloc.c:4568 alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab mm/slub.c:2017 [inline] new_slab+0x283/0x3c0 mm/slub.c:2070 ___slab_alloc+0x979/0x1500 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x131/0x310 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0x4c/0x90 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] __vmalloc_area_node mm/vmalloc.c:3125 [inline] __vmalloc_node_range+0x3e9/0x1540 mm/vmalloc.c:3320 __vmalloc_node mm/vmalloc.c:3385 [inline] vzalloc+0x6b/0x80 mm/vmalloc.c:3458 alloc_counters net/ipv4/netfilter/ip_tables.c:799 [inline] compat_copy_entries_to_user net/ipv4/netfilter/ip_tables.c:1553 [inline] compat_get_entries+0x3a9/0x7d0 net/ipv4/netfilter/ip_tables.c:1596 do_ipt_get_ctl+0x596/0xaa0 net/ipv4/netfilter/ip_tables.c:1657 nf_getsockopt+0x76/0xe0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x186/0x1d0 net/ipv4/ip_sockglue.c:1781 tcp_getsockopt+0x97/0xf0 net/ipv4/tcp.c:4362 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1137 [inline] free_unref_page_prepare+0x4fa/0xaa0 mm/page_alloc.c:2347 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2487 vfree+0x181/0x7a0 mm/vmalloc.c:2842 compat_copy_entries_to_user net/ipv4/netfilter/arp_tables.c:1355 [inline] compat_get_entries+0x511/0x710 net/ipv4/netfilter/arp_tables.c:1390 do_arpt_get_ctl+0x575/0x9a0 net/ipv4/netfilter/arp_tables.c:1450 nf_getsockopt+0x76/0xe0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x186/0x1d0 net/ipv4/ip_sockglue.c:1781 tcp_getsockopt+0x97/0xf0 net/ipv4/tcp.c:4362 do_sock_getsockopt+0x2e1/0x6c0 net/socket.c:2373 __sys_getsockopt+0x1a3/0x270 net/socket.c:2402 __do_compat_sys_socketcall+0x428/0x700 net/compat.c:494 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x62/0xe0 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x70/0x7a Memory state around the buggy address: ffff88807cf54800: fc fc fc fc fb fc fc fc fc fa fc fc fc fc 05 fc ffff88807cf54880: fc fc fc 00 fc fc fc fc fa fc fc fc fc fb fc fc >ffff88807cf54900: fc fc 07 fc fc fc fc fb fc fc fc fc 04 fc fc fc ^ ffff88807cf54980: fc fb fc fc fc fc 05 fc fc fc fc fa fc fc fc fc ffff88807cf54a00: 05 fc fc fc fc fa fc fc fc fc fa fc fc fc fc 05 ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi