================================================================== BUG: KASAN: use-after-free in udf_get_fileident+0x233/0x250 fs/udf/directory.c:176 Read of size 2 at addr ffff8880976ef5f4 by task syz-executor.4/14082 CPU: 1 PID: 14082 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load_n_noabort+0x8b/0xa0 mm/kasan/report.c:443 udf_get_fileident+0x233/0x250 fs/udf/directory.c:176 udf_fileident_read+0x550/0x1930 fs/udf/directory.c:37 udf_readdir+0x559/0x1350 fs/udf/dir.c:129 iterate_dir+0x473/0x5c0 fs/readdir.c:51 __do_sys_getdents fs/readdir.c:271 [inline] __se_sys_getdents+0x175/0x2d0 fs/readdir.c:252 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f41f896e0c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f41f6ee0168 EFLAGS: 00000246 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f41f8a8df80 RCX: 00007f41f896e0c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007f41f89c9ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd9c7a6faf R14: 00007f41f6ee0300 R15: 0000000000022000 Allocated by task 13996: __do_kmalloc_node mm/slab.c:3689 [inline] __kmalloc_node_track_caller+0x4c/0x70 mm/slab.c:3703 __kmalloc_reserve net/core/skbuff.c:137 [inline] __alloc_skb+0xae/0x560 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:995 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1197 [inline] netlink_sendmsg+0x9f6/0xc50 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:661 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227 __sys_sendmsg net/socket.c:2265 [inline] __do_sys_sendmsg net/socket.c:2274 [inline] __se_sys_sendmsg net/socket.c:2272 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 13996: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 skb_free_head net/core/skbuff.c:563 [inline] skb_release_data+0x6de/0x920 net/core/skbuff.c:583 skb_release_all net/core/skbuff.c:640 [inline] __kfree_skb net/core/skbuff.c:654 [inline] consume_skb+0x113/0x3d0 net/core/skbuff.c:714 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x4dd/0x690 net/netlink/af_netlink.c:1351 netlink_sendmsg+0x6c3/0xc50 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:661 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227 __sys_sendmsg net/socket.c:2265 [inline] __do_sys_sendmsg net/socket.c:2274 [inline] __se_sys_sendmsg net/socket.c:2272 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880976ef240 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 948 bytes inside of 1024-byte region [ffff8880976ef240, ffff8880976ef640) The buggy address belongs to the page: page:ffffea00025dbb80 count:1 mapcount:0 mapping:ffff88813bff0ac0 index:0xffff8880976ee4c0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea00025d5308 ffffea00025ef708 ffff88813bff0ac0 raw: ffff8880976ee4c0 ffff8880976ee040 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880976ef480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880976ef500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880976ef580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880976ef600: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880976ef680: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ==================================================================