================================================================== 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 ffff88802fb1b784 by task syz-executor.4/1576 CPU: 0 PID: 1576 Comm: syz-executor.4 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_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f5a9867cce9 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:00007f5a994670c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8 RAX: ffffffffffffffda RBX: 00007f5a9879bf80 RCX: 00007f5a9867cce9 RDX: 0000000020000080 RSI: 0000000000000000 RDI: 00000000200003c0 RBP: 00007f5a986c947a R08: 0000000037327f4e R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f5a9879bf80 R15: 00007ffdfb99b518 Allocated by task 1576: 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+0xa3/0xb0 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_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b The buggy address belongs to the object at ffff88802fb1b780 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes to the right of allocated 4-byte region [ffff88802fb1b780, ffff88802fb1b784) The buggy address belongs to the physical page: page:ffffea0000bec6c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802fb1bfc1 pfn:0x2fb1b flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0x36() raw: 00fff00000000800 ffff888013040100 ffffea000070ec90 ffffea0000e5fa10 raw: ffff88802fb1bfc1 ffff88802fb1b000 0000000100000036 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 0x342040(__GFP_IO|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 25073, tgid 25073 (syz-executor.4), ts 2623112277681, free_ts 2623107861357 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_node include/linux/gfp.h:238 [inline] kmem_getpages mm/slab.c:1356 [inline] cache_grow_begin+0x99/0x3a0 mm/slab.c:2550 cache_alloc_refill+0x295/0x3b0 mm/slab.c:2923 ____cache_alloc mm/slab.c:2999 [inline] ____cache_alloc mm/slab.c:2982 [inline] __do_cache_alloc mm/slab.c:3182 [inline] slab_alloc_node mm/slab.c:3230 [inline] __kmem_cache_alloc_node+0x3ba/0x460 mm/slab.c:3521 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0x49/0x90 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] tomoyo_encode2+0x100/0x3d0 security/tomoyo/realpath.c:45 tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80 tomoyo_path_perm+0x39d/0x450 security/tomoyo/file.c:831 tomoyo_path_symlink+0x98/0xe0 security/tomoyo/tomoyo.c:211 security_path_symlink+0x101/0x160 security/security.c:1786 do_symlinkat+0x10e/0x310 fs/namei.c:4488 __do_sys_symlinkat fs/namei.c:4506 [inline] __se_sys_symlinkat fs/namei.c:4503 [inline] __x64_sys_symlinkat+0x97/0xc0 fs/namei.c:4503 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+0x63/0x6b 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 skb_free_frag include/linux/skbuff.h:3260 [inline] skb_free_head+0xa6/0x1b0 net/core/skbuff.c:960 skb_release_data+0x5ba/0x870 net/core/skbuff.c:992 skb_release_all net/core/skbuff.c:1058 [inline] __kfree_skb+0x51/0x70 net/core/skbuff.c:1072 tcp_data_queue+0x17f7/0x5190 net/ipv4/tcp_input.c:5164 tcp_rcv_established+0x8ba/0x20e0 net/ipv4/tcp_input.c:6177 tcp_v4_do_rcv+0x68c/0xa10 net/ipv4/tcp_ipv4.c:1906 tcp_v4_rcv+0x3892/0x3b40 net/ipv4/tcp_ipv4.c:2329 ip_protocol_deliver_rcu+0x9f/0x480 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2e4/0x510 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] ip_local_deliver+0x18e/0x1f0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_sublist_rcv_finish+0x99/0x2e0 net/ipv4/ip_input.c:580 ip_list_rcv_finish.constprop.0+0x560/0x720 net/ipv4/ip_input.c:631 ip_sublist_rcv net/ipv4/ip_input.c:639 [inline] ip_list_rcv+0x339/0x440 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5575 [inline] __netif_receive_skb_list_core+0x52c/0x8a0 net/core/dev.c:5623 Memory state around the buggy address: ffff88802fb1b680: 00 00 00 00 fc fc fc fc 00 fc fc fc fc fc fc fc ffff88802fb1b700: 00 00 00 00 fc fc fc fc 00 fc fc fc fc fc fc fc >ffff88802fb1b780: 04 fc fc fc fc fc fc fc fa fb fb fb fc fc fc fc ^ ffff88802fb1b800: fb fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ffff88802fb1b880: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc ==================================================================