UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2020/09/19 18:44 (1000) ================================================================== BUG: KASAN: use-after-free in udf_get_fileident+0x1ea/0x200 fs/udf/directory.c:178 Read of size 2 at addr ffff8880980024fc by task syz-executor244/7960 CPU: 1 PID: 7960 Comm: syz-executor244 Not tainted 4.14.266-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load_n_noabort+0x6b/0x80 mm/kasan/report.c:440 udf_get_fileident+0x1ea/0x200 fs/udf/directory.c:178 udf_fileident_read+0x4b9/0x1840 fs/udf/directory.c:36 udf_readdir+0x4d0/0x11f0 fs/udf/dir.c:129 iterate_dir+0x1a0/0x5e0 fs/readdir.c:52 SYSC_getdents64 fs/readdir.c:358 [inline] SyS_getdents64+0x125/0x230 fs/readdir.c:339 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7efd8c27c5b9 RSP: 002b:00007ffd8620d638 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007efd8c27c5b9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007efd8c23be50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007efd8c23bee0 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6234: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x131/0x3d0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] kernfs_fop_open+0x266/0xc40 fs/kernfs/file.c:648 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 6234: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 kernfs_fop_release+0x10e/0x180 fs/kernfs/file.c:783 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff888098002340 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 444 bytes inside of 512-byte region [ffff888098002340, ffff888098002540) The buggy address belongs to the page: page:ffffea0002600080 count:1 mapcount:0 mapping:ffff8880980020c0 index:0xffff888098002340 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffff8880980020c0 ffff888098002340 0000000100000005 raw: ffffea00025bd9a0 ffff88813fe64738 ffff88813fe74940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888098002380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888098002400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888098002480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888098002500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888098002580: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ==================================================================