================================================================== BUG: KASAN: slab-out-of-bounds in dns_resolver_preparse+0xcb3/0xd30 net/dns_resolver/dns_key.c:127 Read of size 1 at addr ffff888028cdffcc by task syz-executor.3/8653 CPU: 0 PID: 8653 Comm: syz-executor.3 Not tainted 6.7.0-rc7-syzkaller-00003-gfbafc3e621c3 #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+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x142/0x170 mm/kasan/report.c:588 dns_resolver_preparse+0xcb3/0xd30 net/dns_resolver/dns_key.c:127 __key_create_or_update+0x47f/0xc40 security/keys/key.c:842 key_create_or_update+0x42/0x60 security/keys/key.c:1007 __do_sys_add_key security/keys/keyctl.c:134 [inline] __se_sys_add_key+0x33f/0x480 security/keys/keyctl.c:74 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f460467cce9 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:00007f46053b40c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8 RAX: ffffffffffffffda RBX: 00007f460479bf80 RCX: 00007f460467cce9 RDX: 0000000020000080 RSI: 0000000020000040 RDI: 00000000200003c0 RBP: 00007f46046c947a R08: 0000000030e2edc9 R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f460479bf80 R15: 00007ffce2befb58 Allocated by task 8653: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc_node+0xb3/0x190 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] kvmalloc_node+0x72/0x180 mm/util.c:617 kvmalloc include/linux/slab.h:738 [inline] __do_sys_add_key security/keys/keyctl.c:116 [inline] __se_sys_add_key+0x270/0x480 security/keys/keyctl.c:74 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b The buggy address belongs to the object at ffff888028cdffc8 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 [ffff888028cdffc8, ffff888028cdffcc) The buggy address belongs to the physical page: page:ffffea0000a337c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28cdf flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888012c41280 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 5644, tgid 5642 (syz-executor.3), ts 317149092214, free_ts 317141029465 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0x33ea/0x3570 mm/page_alloc.c:3312 __alloc_pages+0x255/0x680 mm/page_alloc.c:4568 alloc_pages_mpol+0x3de/0x640 mm/mempolicy.c:2133 alloc_slab_page+0x6a/0x170 mm/slub.c:1870 allocate_slab mm/slub.c:2017 [inline] new_slab+0x84/0x2f0 mm/slub.c:2070 ___slab_alloc+0xc8a/0x1330 mm/slub.c:3223 __slab_alloc mm/slub.c:3322 [inline] __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x21d/0x300 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0xa2/0x190 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] __vmalloc_area_node mm/vmalloc.c:3125 [inline] __vmalloc_node_range+0x5f9/0x14a0 mm/vmalloc.c:3320 __vmalloc_node mm/vmalloc.c:3385 [inline] __vmalloc+0x79/0x90 mm/vmalloc.c:3399 kvm_alloc_memslot_metadata arch/x86/kvm/x86.c:12706 [inline] kvm_arch_prepare_memory_region+0x2aa/0xdc0 arch/x86/kvm/x86.c:12776 kvm_prepare_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1642 [inline] kvm_set_memslot+0x560/0x1170 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1872 __kvm_set_memory_region+0x759/0x900 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2039 kvm_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:2052 [inline] kvm_vm_ioctl_set_memory_region+0x6d/0xa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2064 kvm_vm_ioctl+0x899/0xb50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4816 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+0x931/0xa60 mm/page_alloc.c:2347 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487 tlb_batch_list_free mm/mmu_gather.c:114 [inline] tlb_finish_mmu+0x11f/0x1f0 mm/mmu_gather.c:395 exit_mmap+0x4d3/0xc60 mm/mmap.c:3321 __mmput+0x115/0x3c0 kernel/fork.c:1349 exit_mm+0x21f/0x300 kernel/exit.c:567 do_exit+0x9af/0x2740 kernel/exit.c:856 do_group_exit+0x206/0x2c0 kernel/exit.c:1018 __do_sys_exit_group kernel/exit.c:1029 [inline] __se_sys_exit_group kernel/exit.c:1027 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1027 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Memory state around the buggy address: ffff888028cdfe80: fc fa fc fc fc fc 05 fc fc fc fc fa fc fc fc fc ffff888028cdff00: fa fc fc fc fc fa fc fc fc fc fa fc fc fc fc 05 >ffff888028cdff80: fc fc fc fc fb fc fc fc fc 04 fc fc fc fc fc fc ^ ffff888028ce0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888028ce0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================