netlink: 8 bytes leftover after parsing attributes in process `syz-executor3'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor3'. ================================================================== BUG: KASAN: slab-out-of-bounds in end_requests+0x37b/0x460 fs/fuse/dev.c:2042 Write of size 4 at addr ffff8801c65dbfe4 by task syz-executor7/19431 CPU: 1 PID: 19431 Comm: syz-executor7 Not tainted 4.18.0-rc7+ #175 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+0x1c9/0x2b4 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_store4_noabort+0x17/0x20 mm/kasan/report.c:437 end_requests+0x37b/0x460 fs/fuse/dev.c:2042 fuse_dev_release+0x18c/0x2e0 fs/fuse/dev.c:2154 __fput+0x355/0x8b0 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x1ec/0x2a0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:192 [inline] exit_to_usermode_loop+0x313/0x370 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456b29 Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0292bf2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: 0000000000000030 RBX: 00007f0292bf36d4 RCX: 0000000000456b29 RDX: 0000000000001000 RSI: 0000000020001000 RDI: 0000000000000014 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d2b40 R14: 00000000004c7b8b R15: 0000000000000000 Allocated by task 19431: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620 kmalloc include/linux/slab.h:513 [inline] kzalloc include/linux/slab.h:707 [inline] fuse_dev_alloc+0xbd/0x500 fs/fuse/inode.c:1023 fuse_fill_super+0xd39/0x1ee0 fs/fuse/inode.c:1121 mount_nodev+0x6b/0x110 fs/super.c:1220 fuse_mount+0x2c/0x40 fs/fuse/inode.c:1210 mount_fs+0xae/0x328 fs/super.c:1277 vfs_kern_mount.part.34+0xdc/0x4e0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:1027 [inline] do_new_mount fs/namespace.c:2518 [inline] do_mount+0x581/0x30e0 fs/namespace.c:2848 ksys_mount+0x12d/0x140 fs/namespace.c:3064 __do_sys_mount fs/namespace.c:3078 [inline] __se_sys_mount fs/namespace.c:3075 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 4453: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 __rcu_reclaim kernel/rcu/rcu.h:173 [inline] rcu_do_batch kernel/rcu/tree.c:2558 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2818 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2785 [inline] rcu_process_callbacks+0x1004/0x1850 kernel/rcu/tree.c:2802 __do_softirq+0x2e8/0xb17 kernel/softirq.c:292 The buggy address belongs to the object at ffff8801c65dbf00 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 100 bytes to the right of 128-byte region [ffff8801c65dbf00, ffff8801c65dbf80) The buggy address belongs to the page: page:ffffea00071976c0 count:1 mapcount:0 mapping:ffff8801dac00640 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea0006dbe3c8 ffffea0006dd72c8 ffff8801dac00640 raw: 0000000000000000 ffff8801c65db000 0000000100000015 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c65dbe80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8801c65dbf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc >ffff8801c65dbf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801c65dc000: fb fb fb fb fb fb fb fc fc fc fc fb fb fb fb fb ffff8801c65dc080: fb fb fc fc fc fc fb fb fb fb fb fb fb fc fc fc ==================================================================