================================================================== BUG: KASAN: slab-out-of-bounds in dns_resolver_preparse+0x910/0x9b0 net/dns_resolver/dns_key.c:127 Read of size 1 at addr ffff888014fbcd24 by task syz-executor.6/4880 CPU: 0 PID: 4880 Comm: syz-executor.6 Not tainted 5.10.207 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 print_address_description.constprop.0+0x1c/0x220 mm/kasan/report.c:377 __kasan_report mm/kasan/report.c:537 [inline] kasan_report.cold+0x37/0x7c mm/kasan/report.c:554 dns_resolver_preparse+0x910/0x9b0 net/dns_resolver/dns_key.c:127 key_create_or_update+0x3e0/0xc30 security/keys/key.c:859 __do_sys_add_key+0x215/0x430 security/keys/keyctl.c:134 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x62/0xc7 RIP: 0033:0x7fead7f3fb19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fead54b5188 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8 RAX: ffffffffffffffda RBX: 00007fead8052f60 RCX: 00007fead7f3fb19 RDX: 0000000020000000 RSI: 0000000000000000 RDI: 0000000020000200 RBP: 00007fead7f99f6d R08: fffffffffffffffb R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcf769fe8f R14: 00007fead54b5300 R15: 0000000000022000 Allocated by task 4880: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc9/0xd0 mm/kasan/common.c:461 kmalloc_node include/linux/slab.h:575 [inline] kvmalloc_node+0x119/0x170 mm/util.c:607 kvmalloc include/linux/mm.h:765 [inline] __do_sys_add_key+0x311/0x430 security/keys/keyctl.c:116 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x62/0xc7 The buggy address belongs to the object at ffff888014fbcd20 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 4 bytes inside of 8-byte region [ffff888014fbcd20, ffff888014fbcd28) The buggy address belongs to the page: page:00000000118dd0ef refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14fbc flags: 0x100000000000200(slab) raw: 0100000000000200 ffffea000053f100 0000000900000009 ffff888008041c80 raw: 0000000000000000 0000000080660066 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888014fbcc00: fc fb fc fc fc fc fb fc fc fc fc fa fc fc fc fc ffff888014fbcc80: fa fc fc fc fc 00 fc fc fc fc fb fc fc fc fc fb >ffff888014fbcd00: fc fc fc fc 04 fc fc fc fc fb fc fc fc fc fb fc ^ ffff888014fbcd80: fc fc fc fa fc fc fc fc fb fc fc fc fc fb fc fc ffff888014fbce00: fc fc fb fc fc fc fc fb fc fc fc fc fb fc fc fc ================================================================== EXT4-fs (loop2): mounted filesystem without journal. Opts: ,errors=continue