================================================================== BUG: KASAN: slab-out-of-bounds in squashfs_get_id+0x1ae/0x1d0 fs/squashfs/id.c:51 Read of size 8 at addr ffff8880b4babc78 by task syz-executor.4/26152 CPU: 1 PID: 26152 Comm: syz-executor.4 Not tainted 4.19.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2fe lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1c7 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 squashfs_get_id+0x1ae/0x1d0 fs/squashfs/id.c:51 squashfs_new_inode fs/squashfs/inode.c:68 [inline] squashfs_read_inode+0x1ee/0x1b40 fs/squashfs/inode.c:133 squashfs_fill_super+0x1655/0x1c00 fs/squashfs/super.c:318 mount_bdev+0x2fc/0x3b0 fs/super.c:1158 mount_fs+0xa3/0x30c fs/super.c:1261 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961 vfs_kern_mount fs/namespace.c:951 [inline] do_new_mount fs/namespace.c:2469 [inline] do_mount+0x113c/0x2f10 fs/namespace.c:2799 ksys_mount+0xcf/0x130 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xba/0x150 fs/namespace.c:3026 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460c6a Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 ad 89 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 8a 89 fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007fc46e2d7a78 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fc46e2d7b10 RCX: 0000000000460c6a RDX: 0000000020000000 RSI: 00000000200000c0 RDI: 00007fc46e2d7ad0 RBP: 00007fc46e2d7ad0 R08: 00007fc46e2d7b10 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000 R13: 00000000200000c0 R14: 0000000020000200 R15: 0000000020010200 Allocated by task 26152: __do_kmalloc mm/slab.c:3727 [inline] __kmalloc+0x15a/0x3c0 mm/slab.c:3736 kmalloc_array include/linux/slab.h:637 [inline] kcalloc include/linux/slab.h:648 [inline] squashfs_read_data+0x161/0x13b0 fs/squashfs/block.c:100 squashfs_read_table+0x184/0x1e3 fs/squashfs/cache.c:445 squashfs_read_id_index_table+0xab/0x120 fs/squashfs/id.c:90 squashfs_fill_super+0xcfb/0x1c00 fs/squashfs/super.c:246 mount_bdev+0x2fc/0x3b0 fs/super.c:1158 mount_fs+0xa3/0x30c fs/super.c:1261 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961 vfs_kern_mount fs/namespace.c:951 [inline] do_new_mount fs/namespace.c:2469 [inline] do_mount+0x113c/0x2f10 fs/namespace.c:2799 ksys_mount+0xcf/0x130 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xba/0x150 fs/namespace.c:3026 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 26152: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 squashfs_read_data+0xa72/0x13b0 fs/squashfs/block.c:205 squashfs_read_table+0x184/0x1e3 fs/squashfs/cache.c:445 squashfs_read_id_index_table+0xab/0x120 fs/squashfs/id.c:90 squashfs_fill_super+0xcfb/0x1c00 fs/squashfs/super.c:246 mount_bdev+0x2fc/0x3b0 fs/super.c:1158 mount_fs+0xa3/0x30c fs/super.c:1261 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961 vfs_kern_mount fs/namespace.c:951 [inline] do_new_mount fs/namespace.c:2469 [inline] do_mount+0x113c/0x2f10 fs/namespace.c:2799 ksys_mount+0xcf/0x130 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xba/0x150 fs/namespace.c:3026 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 ffff8880b4babc40 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 24 bytes to the right of 32-byte region [ffff8880b4babc40, ffff8880b4babc60) The buggy address belongs to the page: page:ffffea0002d2eac0 count:1 mapcount:0 mapping:ffff88813bff01c0 index:0xffff8880b4babfc1 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea0002cbe6c8 ffffea0002a7b108 ffff88813bff01c0 raw: ffff8880b4babfc1 ffff8880b4bab000 000000010000003f 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880b4babb00: 05 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc ffff8880b4babb80: 00 fc fc fc fc fc fc fc 00 00 fc fc fc fc fc fc >ffff8880b4babc00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff8880b4babc80: fb fb fb fb fc fc fc fc 00 fc fc fc fc fc fc fc ffff8880b4babd00: fb fb fb fb fc fc fc fc 05 fc fc fc fc fc fc fc ==================================================================