================================================================== BUG: KASAN: use-after-free in ceph_destroy_options+0xda/0x100 net/ceph/ceph_common.c:283 Read of size 8 at addr ffff88809fae4690 by task syz-executor.3/30713 CPU: 1 PID: 30713 Comm: syz-executor.3 Not tainted 4.14.184-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+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2b9 mm/kasan/report.c:393 ceph_destroy_options+0xda/0x100 net/ceph/ceph_common.c:283 ceph_mount+0xd43/0x181c fs/ceph/super.c:1036 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x3c9/0x25e0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45ca69 RSP: 002b:00007f534295ec78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000004f6b00 RCX: 000000000045ca69 RDX: 0000000020000040 RSI: 00000000200000c0 RDI: 0000000020000480 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000768 R14: 00000000004ca5d3 R15: 00007f534295f6d4 Allocated by task 30713: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc.part.0+0x4f/0xd0 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x14d/0x3f0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] ceph_parse_options+0xb8/0xe50 net/ceph/ceph_common.c:349 parse_mount_options fs/ceph/super.c:501 [inline] ceph_mount+0x44f/0x181c fs/ceph/super.c:1025 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x3c9/0x25e0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 30713: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xaf/0x190 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcb/0x260 mm/slab.c:3815 ceph_destroy_client+0x90/0xb0 net/ceph/ceph_common.c:671 create_fs_client fs/ceph/super.c:684 [inline] ceph_mount+0xd1c/0x181c fs/ceph/super.c:1032 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x3c9/0x25e0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff88809fae45c0 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 208 bytes inside of 256-byte region [ffff88809fae45c0, ffff88809fae46c0) The buggy address belongs to the page: page:ffffea00027eb900 count:1 mapcount:0 mapping:ffff88809fae40c0 index:0xffff88809fae4480 flags: 0xfffe0000000100(slab) raw: 00fffe0000000100 ffff88809fae40c0 ffff88809fae4480 0000000100000004 raw: ffffea00015eac60 ffffea00025f7e60 ffff8880aa8007c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809fae4580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff88809fae4600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88809fae4680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff88809fae4700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809fae4780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================