bpfilter: read fail -512 ================================================================== BUG: KASAN: use-after-free in io_is_direct include/linux/fs.h:3192 [inline] BUG: KASAN: use-after-free in iocb_flags include/linux/fs.h:3219 [inline] BUG: KASAN: use-after-free in init_sync_kiocb include/linux/fs.h:1934 [inline] BUG: KASAN: use-after-free in new_sync_write fs/read_write.c:470 [inline] BUG: KASAN: use-after-free in __vfs_write+0x929/0x960 fs/read_write.c:487 Read of size 8 at addr ffff8801d4ff5b68 by task syz-executor3/4552 netlink: 'syz-executor2': attribute type 25 has an invalid length. CPU: 1 PID: 4552 Comm: syz-executor3 Not tainted 4.17.0-rc7+ #82 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+0x1b9/0x294 lib/dump_stack.c:113 netlink: 3 bytes leftover after parsing attributes in process `syz-executor2'. 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_load8_noabort+0x14/0x20 mm/kasan/report.c:433 io_is_direct include/linux/fs.h:3192 [inline] iocb_flags include/linux/fs.h:3219 [inline] init_sync_kiocb include/linux/fs.h:1934 [inline] new_sync_write fs/read_write.c:470 [inline] __vfs_write+0x929/0x960 fs/read_write.c:487 netlink: 'syz-executor2': attribute type 25 has an invalid length. __kernel_write+0x10c/0x380 fs/read_write.c:506 __bpfilter_process_sockopt+0x1d8/0x35b net/bpfilter/bpfilter_kern.c:66 netlink: 3 bytes leftover after parsing attributes in process `syz-executor2'. bpfilter_mbox_request+0x4d/0xb0 net/ipv4/bpfilter/sockopt.c:25 bpfilter_ip_get_sockopt+0x6b/0x90 net/ipv4/bpfilter/sockopt.c:42 ip_getsockopt+0x238/0x2a0 net/ipv4/ip_sockglue.c:1563 tcp_getsockopt+0x93/0xe0 net/ipv4/tcp.c:3543 sock_common_getsockopt+0x9a/0xe0 net/core/sock.c:3018 __sys_getsockopt+0x1a5/0x370 net/socket.c:1940 __do_sys_getsockopt net/socket.c:1951 [inline] __se_sys_getsockopt net/socket.c:1948 [inline] __x64_sys_getsockopt+0xbe/0x150 net/socket.c:1948 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4584ea RSP: 002b:0000000000a3e328 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 0000000000a3e350 RCX: 00000000004584ea RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000013 RBP: 0000000000705f20 R08: 0000000000a3e34c R09: 0000000000004000 R10: 0000000000a3e350 R11: 0000000000000246 R12: 0000000000000013 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000703d60 Allocated by task 2199: 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 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554 alloc_inode+0xb2/0x190 fs/inode.c:212 new_inode_pseudo+0x69/0x1a0 fs/inode.c:895 get_pipe_inode fs/pipe.c:704 [inline] create_pipe_files+0x90/0x940 fs/pipe.c:745 umh_pipe_setup+0xac/0x430 kernel/umh.c:431 call_usermodehelper_exec_async+0x3c0/0x9e0 kernel/umh.c:93 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Freed by task 2199: 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] kmem_cache_free+0x86/0x2d0 mm/slab.c:3756 free_inode_nonrcu+0x1c/0x20 fs/inode.c:230 destroy_inode+0x151/0x1f0 fs/inode.c:267 evict+0x5cd/0x960 fs/inode.c:575 iput_final fs/inode.c:1520 [inline] iput+0x62d/0xa80 fs/inode.c:1546 dentry_unlink_inode+0x49a/0x620 fs/dcache.c:376 __dentry_kill+0x444/0x770 fs/dcache.c:568 dentry_kill+0xc9/0x5a0 fs/dcache.c:686 dput.part.27+0x648/0x7b0 fs/dcache.c:850 dput+0x1f/0x30 fs/dcache.c:830 __fput+0x552/0x890 fs/file_table.c:227 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x1e4/0x290 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x1aee/0x2730 kernel/exit.c:865 do_group_exit+0x16f/0x430 kernel/exit.c:968 __do_sys_exit_group kernel/exit.c:979 [inline] __se_sys_exit_group kernel/exit.c:977 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801d4ff5960 which belongs to the cache inode_cache of size 944 The buggy address is located 520 bytes inside of 944-byte region [ffff8801d4ff5960, ffff8801d4ff5d10) The buggy address belongs to the page: page:ffffea000753fd40 count:1 mapcount:0 mapping:ffff8801d4ff5100 index:0xffff8801d4ff5ffd flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801d4ff5100 ffff8801d4ff5ffd 0000000100000003 raw: ffffea000753fa20 ffffea0007380520 ffff8801da988ac0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d4ff5a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d4ff5a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801d4ff5b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801d4ff5b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d4ff5c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================