EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue ================================================================== BUG: KASAN: use-after-free in memcpy include/linux/string.h:372 [inline] BUG: KASAN: use-after-free in ext4_write_inline_data+0x2ae/0x380 fs/ext4/inline.c:251 Write of size 70 at addr ffff8880b61074ef by task syz-executor568/7952 CPU: 0 PID: 7952 Comm: syz-executor568 Not tainted 4.14.218-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+0x1b2/0x281 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351 kasan_report+0x6f/0x80 mm/kasan/report.c:409 memcpy+0x35/0x50 mm/kasan/kasan.c:303 memcpy include/linux/string.h:372 [inline] ext4_write_inline_data+0x2ae/0x380 fs/ext4/inline.c:251 ext4_write_inline_data_end+0x1d3/0x490 fs/ext4/inline.c:760 ext4_write_end+0x18d/0xca0 fs/ext4/inode.c:1423 ext4_da_write_end+0x6da/0x8e0 fs/ext4/inode.c:3178 generic_perform_write+0x268/0x420 mm/filemap.c:3066 __generic_file_write_iter+0x227/0x590 mm/filemap.c:3180 ext4_file_write_iter+0x276/0xd20 fs/ext4/file.c:270 call_write_iter include/linux/fs.h:1778 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x44c/0x630 fs/read_write.c:482 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x44a509 RSP: 002b:00007f0582f64208 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000004cd428 RCX: 000000000044a509 RDX: 0000000000000082 RSI: 0000000020000180 RDI: 0000000000000008 RBP: 00000000004cd420 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004cd42c R13: 00007ffc529d143f R14: 00007f0582f64300 R15: 0000000000022000 Allocated by task 1: 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 include/linux/slab.h:493 [inline] do_tty_write drivers/tty/tty_io.c:941 [inline] tty_write+0x4e0/0x740 drivers/tty/tty_io.c:1043 redirected_tty_write+0x9c/0xb0 drivers/tty/tty_io.c:1064 do_loop_readv_writev fs/read_write.c:698 [inline] do_loop_readv_writev fs/read_write.c:682 [inline] do_iter_write+0x3da/0x550 fs/read_write.c:956 vfs_writev+0x125/0x290 fs/read_write.c:999 do_writev+0xfc/0x2c0 fs/read_write.c:1034 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 3517: 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 free_tty_struct drivers/tty/tty_io.c:172 [inline] release_one_tty+0x2cf/0x3e0 drivers/tty/tty_io.c:1455 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 The buggy address belongs to the object at ffff8880b6107200 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 751 bytes inside of 1024-byte region [ffff8880b6107200, ffff8880b6107600) The buggy address belongs to the page: page:ffffea0002d84180 count:1 mapcount:0 mapping:ffff8880b6106000 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffff8880b6106000 0000000000000000 0000000100000007 raw: ffffea00025bb920 ffffea00025bf6a0 ffff88813fe80ac0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880b6107380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880b6107400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880b6107480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880b6107500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880b6107580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================