================================================================== BUG: KASAN: slab-out-of-bounds in squashfs_inode_lookup fs/squashfs/export.c:57 [inline] BUG: KASAN: slab-out-of-bounds in squashfs_export_iget+0x22f/0x250 fs/squashfs/export.c:82 Read of size 8 at addr ffff8880b2f75af8 by task syz-executor936/7988 CPU: 0 PID: 7988 Comm: syz-executor936 Not tainted 4.14.206-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+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 squashfs_inode_lookup fs/squashfs/export.c:57 [inline] squashfs_export_iget+0x22f/0x250 fs/squashfs/export.c:82 squashfs_fh_to_dentry fs/squashfs/export.c:97 [inline] squashfs_fh_to_dentry+0x5f/0x90 fs/squashfs/export.c:90 exportfs_decode_fh+0x113/0x6bc fs/exportfs/expfs.c:433 do_handle_to_path fs/fhandle.c:153 [inline] handle_to_path fs/fhandle.c:208 [inline] do_handle_open+0x248/0x570 fs/fhandle.c:224 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4443e9 RSP: 002b:00007ffc966f52b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000130 RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 00000000004443e9 RDX: 0000000000490400 RSI: 0000000020000100 RDI: 0000000000000005 RBP: 00000000006cf018 R08: 00007ffc00000015 R09: 00000000004002e0 R10: 00007ffc966f5160 R11: 0000000000000246 R12: 0000000000401fd0 R13: 0000000000402060 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 7988: 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 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15a/0x400 mm/slab.c:3729 kmalloc_array include/linux/slab.h:607 [inline] kcalloc include/linux/slab.h:618 [inline] squashfs_read_table+0x76/0x18d fs/squashfs/cache.c:430 squashfs_read_inode_lookup_table+0x95/0xe0 fs/squashfs/export.c:144 squashfs_fill_super+0xcef/0x1aa0 fs/squashfs/super.c:263 mount_bdev+0x2b3/0x360 fs/super.c:1134 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 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 7988: 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 squashfs_read_table+0x127/0x18d fs/squashfs/cache.c:448 squashfs_read_inode_lookup_table+0x95/0xe0 fs/squashfs/export.c:144 squashfs_fill_super+0xcef/0x1aa0 fs/squashfs/super.c:263 mount_bdev+0x2b3/0x360 fs/super.c:1134 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 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 ffff8880b2f75ac0 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 24 bytes to the right of 32-byte region [ffff8880b2f75ac0, ffff8880b2f75ae0) The buggy address belongs to the page: page:ffffea0002cbdd40 count:1 mapcount:0 mapping:ffff8880b2f75000 index:0xffff8880b2f75fc1 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffff8880b2f75000 ffff8880b2f75fc1 000000010000003f raw: ffffea0002cbd8e0 ffff88813fe80248 ffff88813fe821c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880b2f75980: 00 fc fc fc fc fc fc fc 00 fc fc fc fc fc fc fc ffff8880b2f75a00: 00 fc fc fc fc fc fc fc 00 fc fc fc fc fc fc fc >ffff8880b2f75a80: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff8880b2f75b00: 00 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc ffff8880b2f75b80: fb fb fb fb fc fc fc fc 00 fc fc fc fc fc fc fc ==================================================================