================================================================== BUG: KASAN: use-after-free in memset include/linux/string.h:344 [inline] BUG: KASAN: use-after-free in __ext4_expand_extra_isize+0x1ab/0x290 fs/ext4/inode.c:5948 Write of size 479 at addr ffff88806ebc7ea0 by task syz-executor.5/24713 CPU: 1 PID: 24713 Comm: syz-executor.5 Not tainted 5.3.0-rc7+ #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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x17 mm/kasan/common.c:618 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 memset+0x24/0x40 mm/kasan/common.c:105 memset include/linux/string.h:344 [inline] __ext4_expand_extra_isize+0x1ab/0x290 fs/ext4/inode.c:5948 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6000 [inline] ext4_mark_inode_dirty+0x74e/0x9b0 fs/ext4/inode.c:6076 ext4_dirty_inode+0x8f/0xc0 fs/ext4/inode.c:6110 __mark_inode_dirty+0x68e/0x1390 fs/fs-writeback.c:2170 generic_update_time+0x21c/0x370 fs/inode.c:1664 update_time fs/inode.c:1680 [inline] touch_atime+0x23c/0x2a0 fs/inode.c:1751 get_link fs/namei.c:1055 [inline] trailing_symlink+0x2e3/0x990 fs/namei.c:2261 path_mountpoint+0x865/0x1e60 fs/namei.c:2694 filename_mountpoint+0x190/0x3c0 fs/namei.c:2715 user_path_mountpoint_at+0x3a/0x50 fs/namei.c:2745 ksys_umount+0x167/0xf00 fs/namespace.c:1680 __do_sys_umount fs/namespace.c:1706 [inline] __se_sys_umount fs/namespace.c:1704 [inline] __x64_sys_umount+0x54/0x80 fs/namespace.c:1704 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c317 Code: 64 89 04 25 d0 02 00 00 58 5f ff d0 48 89 c7 e8 2f be ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 9d 8d fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffd1468b418 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 0000000000079504 RCX: 000000000045c317 RDX: 0000000000403520 RSI: 0000000000000002 RDI: 00007ffd1468b4c0 RBP: 0000000000000210 R08: 0000000000000000 R09: 0000000000000010 R10: 000000000000000a R11: 0000000000000202 R12: 00007ffd1468c550 R13: 0000555555a60940 R14: 0000000000000000 R15: 00007ffd1468c550 The buggy address belongs to the page: page:ffffea0001baf1c0 refcount:2 mapcount:0 mapping:ffff88821a2b0a98 index:0x469 def_blk_aops flags: 0x1fffc000000203a(referenced|dirty|lru|active|private) raw: 01fffc000000203a ffffea00020c2208 ffff88808bf54930 ffff88821a2b0a98 raw: 0000000000000469 ffff888092e029d8 00000002ffffffff ffff88808cd64e40 page dumped because: kasan: bad access detected page->mem_cgroup:ffff88808cd64e40 Memory state around the buggy address: ffff88806ebc7f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88806ebc7f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88806ebc8000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88806ebc8080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88806ebc8100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================