================================================================== BUG: KASAN: use-after-free in squashfs_get_id+0x1ae/0x1d0 fs/squashfs/id.c:51 Read of size 8 at addr ffff8880a9f9d400 by task syz-executor999/8155 CPU: 0 PID: 8155 Comm: syz-executor999 Not tainted 4.19.157-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:64 [inline] squashfs_read_inode+0x1b4/0x1b40 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: 0033:0x446d1a Code: b8 08 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 fd ad 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 da ad fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007ffeaacb9378 EFLAGS: 00000293 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007ffeaacb93d0 RCX: 0000000000446d1a RDX: 0000000020000000 RSI: 00000000200000c0 RDI: 00007ffeaacb9390 RBP: 00007ffeaacb9390 R08: 00007ffeaacb93d0 R09: 00007ffe00000015 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 0000000000000004 R14: 0000000000000003 R15: 0000000000000003 Allocated by task 14: __do_kmalloc mm/slab.c:3727 [inline] __kmalloc+0x15a/0x3c0 mm/slab.c:3736 kmalloc include/linux/slab.h:520 [inline] kzalloc include/linux/slab.h:709 [inline] rh_call_control drivers/usb/core/hcd.c:510 [inline] rh_urb_enqueue drivers/usb/core/hcd.c:838 [inline] usb_hcd_submit_urb+0x656/0x23c0 drivers/usb/core/hcd.c:1651 usb_submit_urb+0xb2f/0x13b0 drivers/usb/core/urb.c:571 usb_start_wait_urb+0x108/0x4c0 drivers/usb/core/message.c:57 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:152 get_port_status drivers/usb/core/hub.c:571 [inline] hub_ext_port_status+0x112/0x4b0 drivers/usb/core/hub.c:588 hub_port_status drivers/usb/core/hub.c:610 [inline] hub_activate+0x515/0x19b0 drivers/usb/core/hub.c:1092 process_one_work+0x864/0x1570 kernel/workqueue.c:2155 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Freed by task 14: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 rh_call_control drivers/usb/core/hcd.c:728 [inline] rh_urb_enqueue drivers/usb/core/hcd.c:838 [inline] usb_hcd_submit_urb+0xb93/0x23c0 drivers/usb/core/hcd.c:1651 usb_submit_urb+0xb2f/0x13b0 drivers/usb/core/urb.c:571 usb_start_wait_urb+0x108/0x4c0 drivers/usb/core/message.c:57 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:152 get_port_status drivers/usb/core/hub.c:571 [inline] hub_ext_port_status+0x112/0x4b0 drivers/usb/core/hub.c:588 hub_port_status drivers/usb/core/hub.c:610 [inline] hub_activate+0x515/0x19b0 drivers/usb/core/hub.c:1092 process_one_work+0x864/0x1570 kernel/workqueue.c:2155 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 The buggy address belongs to the object at ffff8880a9f9d400 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of 32-byte region [ffff8880a9f9d400, ffff8880a9f9d420) The buggy address belongs to the page: page:ffffea0002a7e740 count:1 mapcount:0 mapping:ffff88813bff01c0 index:0xffff8880a9f9dfc1 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea0002a71348 ffff88813bff1238 ffff88813bff01c0 raw: ffff8880a9f9dfc1 ffff8880a9f9d000 0000000100000022 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a9f9d300: fb fb fb fb fc fc fc fc 00 fc fc fc fc fc fc fc ffff8880a9f9d380: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc >ffff8880a9f9d400: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff8880a9f9d480: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8880a9f9d500: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ==================================================================