================================================================== 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 ffff888026678cac by task syz-executor.5/20503 CPU: 0 PID: 20503 Comm: syz-executor.5 Not tainted 6.7.0-rc7-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: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: 0033:0x7ff9ad07cce9 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:00007ff9add400c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8 RAX: ffffffffffffffda RBX: 00007ff9ad19bf80 RCX: 00007ff9ad07cce9 RDX: 0000000020001a40 RSI: 0000000020000400 RDI: 00000000200003c0 RBP: 00007ff9ad0c947a R08: 0000000022ca52f1 R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007ff9ad19bf80 R15: 00007ff9ad2bfa48 Allocated by task 20503: 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_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 ffff888026678ca8 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 [ffff888026678ca8, ffff888026678cac) The buggy address belongs to the physical page: page:ffffea0000999e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26678 ksm flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888013041280 ffffea00009d9fc0 dead000000000003 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 6394, tgid 6394 (udevd), ts 426497363527, free_ts 426494183214 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_track_caller+0x4a/0x90 mm/slab_common.c:1027 kmemdup+0x29/0x60 mm/util.c:131 kmemdup include/linux/fortify-string.h:761 [inline] shmem_symlink+0x243/0x6e0 mm/shmem.c:3497 vfs_symlink fs/namei.c:4464 [inline] vfs_symlink+0x3e4/0x620 fs/namei.c:4448 do_symlinkat+0x25f/0x310 fs/namei.c:4490 __do_sys_symlink fs/namei.c:4511 [inline] __se_sys_symlink fs/namei.c:4509 [inline] __x64_sys_symlink+0x79/0x90 fs/namei.c:4509 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 tlb_batch_list_free mm/mmu_gather.c:114 [inline] tlb_finish_mmu+0x1a7/0x6f0 mm/mmu_gather.c:395 exit_mmap+0x38b/0xa70 mm/mmap.c:3321 __mmput+0x12a/0x4d0 kernel/fork.c:1349 mmput+0x62/0x70 kernel/fork.c:1371 exit_mm kernel/exit.c:567 [inline] do_exit+0x9a5/0x2ad0 kernel/exit.c:856 do_group_exit+0xd4/0x2a0 kernel/exit.c:1018 get_signal+0x23b5/0x2790 kernel/signal.c:2904 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x121/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1e/0x60 kernel/entry/common.c:296 do_syscall_64+0x4d/0x110 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x63/0x6b Memory state around the buggy address: ffff888026678b80: fc fc 05 fc fc fc fc 05 fc fc fc fc 07 fc fc fc ffff888026678c00: fc fa fc fc fc fc 07 fc fc fc fc 05 fc fc fc fc >ffff888026678c80: fb fc fc fc fc 04 fc fc fc fc 05 fc fc fc fc 00 ^ ffff888026678d00: fc fc fc fc fa fc fc fc fc 06 fc fc fc fc 07 fc ffff888026678d80: fc fc fc 07 fc fc fc fc 05 fc fc fc fc fa fc fc ==================================================================