EXT4-fs (loop1): pa ffff888111c8ef18: logic 256, phys. 385, len 8
EXT4-fs error (device loop1): ext4_mb_release_inode_pa:4902: group 0, free 0, pa_free 1
==================================================================
BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:827 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0xbeb/0xe20 fs/ext4/extents.c:946
Read of size 4 at addr ffff88813989aab4 by task syz.1.3985/14672
CPU: 1 PID: 14672 Comm: syz.1.3985 Tainted: G W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:88
dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
__kasan_report mm/kasan/report.c:427 [inline]
kasan_report+0xf1/0x140 mm/kasan/report.c:444
__asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
ext4_ext_binsearch fs/ext4/extents.c:827 [inline]
ext4_find_extent+0xbeb/0xe20 fs/ext4/extents.c:946
ext4_ext_remove_space+0x2de/0x40d0 fs/ext4/extents.c:2834
ext4_punch_hole+0x77c/0xbd0 fs/ext4/inode.c:4137
ext4_fallocate+0x2b6/0x1de0 fs/ext4/extents.c:4771
vfs_fallocate+0x4b4/0x590 fs/open.c:309
madvise_remove mm/madvise.c:964 [inline]
madvise_vma_behavior mm/madvise.c:988 [inline]
madvise_walk_vmas mm/madvise.c:1218 [inline]
do_madvise+0x1435/0x2420 mm/madvise.c:1396
__do_sys_madvise mm/madvise.c:1409 [inline]
__se_sys_madvise mm/madvise.c:1407 [inline]
__x64_sys_madvise+0xa9/0xc0 mm/madvise.c:1407
x64_sys_call+0x89b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:29
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f722ebdbdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f722d636028 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007f722ee54fa0 RCX: 00007f722ebdbdd9
RDX: 0000000000000009 RSI: 0000000000600003 RDI: 0000200000000000
RBP: 00007f722ec71d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f722ee55038 R14: 00007f722ee54fa0 R15: 00007ffea4bfc848
The buggy address belongs to the page:
page:ffffea0004e62680 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x13989a
flags: 0x4000000000000000(zone=1)
raw: 4000000000000000 ffffea0004e626c8 ffffea0004e62648 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x100cca(GFP_HIGHUSER_MOVABLE), pid 14537, ts 901427604399, free_ts 903622218576
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605
prep_new_page+0x1c/0x110 mm/page_alloc.c:2611
get_page_from_freelist+0x2d3a/0x2dc0 mm/page_alloc.c:4485
__alloc_pages+0x1a2/0x460 mm/page_alloc.c:5822
__alloc_pages_node include/linux/gfp.h:595 [inline]
alloc_pages_node include/linux/gfp.h:609 [inline]
alloc_pages include/linux/gfp.h:622 [inline]
shmem_alloc_page mm/shmem.c:1587 [inline]
shmem_alloc_and_acct_page+0x4a2/0x8d0 mm/shmem.c:1612
shmem_getpage_gfp+0xfe5/0x2310 mm/shmem.c:1908
shmem_getpage mm/shmem.c:152 [inline]
shmem_write_begin+0xce/0x1b0 mm/shmem.c:2476
generic_perform_write+0x2b7/0x690 mm/filemap.c:3870
__generic_file_write_iter+0x268/0x480 mm/filemap.c:3998
generic_file_write_iter+0xa9/0x1d0 mm/filemap.c:4030
call_write_iter include/linux/fs.h:2212 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x835/0xfd0 fs/read_write.c:594
ksys_write+0x149/0x250 fs/read_write.c:647
__do_sys_write fs/read_write.c:659 [inline]
__se_sys_write fs/read_write.c:656 [inline]
__x64_sys_write+0x7b/0x90 fs/read_write.c:656
x64_sys_call+0x8ef/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
free_pages_prepare mm/page_alloc.c:1472 [inline]
free_pcp_prepare mm/page_alloc.c:1544 [inline]
free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534
free_unref_page_list+0x13a/0x9d0 mm/page_alloc.c:3671
release_pages+0x1006/0x1060 mm/swap.c:1015
__pagevec_release+0x71/0xe0 mm/swap.c:1035
pagevec_release include/linux/pagevec.h:81 [inline]
shmem_undo_range+0x595/0x1470 mm/shmem.c:965
shmem_truncate_range mm/shmem.c:1064 [inline]
shmem_evict_inode+0x21a/0xa10 mm/shmem.c:1146
evict+0x4c9/0x8d0 fs/inode.c:650
iput_final fs/inode.c:1779 [inline]
iput+0x635/0x7c0 fs/inode.c:1805
dentry_unlink_inode+0x32f/0x3e0 fs/dcache.c:380
__dentry_kill+0x44f/0x650 fs/dcache.c:586
dentry_kill+0xc0/0x2a0 fs/dcache.c:-1
dput+0x47/0x90 fs/dcache.c:893
__fput+0x580/0x8b0 fs/file_table.c:319
____fput+0x15/0x20 fs/file_table.c:339
task_work_run+0x127/0x190 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
Memory state around the buggy address:
ffff88813989a980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88813989aa00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88813989aa80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff88813989ab00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88813989ab80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
------------[ cut here ]------------
kernel BUG at fs/ext4/extents.c:3189!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 14672 Comm: syz.1.3985 Tainted: G B W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:ext4_split_extent_at+0xe29/0xe50 fs/ext4/extents.c:3189
Code: ff ff 44 89 f1 80 e1 07 fe c1 38 c1 0f 8c fc fb ff ff 4c 89 f7 49 89 d7 e8 64 e4 d2 ff 4c 89 fa e9 e9 fb ff ff e8 07 b1 93 ff <0f> 0b e8 00 b1 93 ff 0f 0b e8 f9 b0 93 ff 0f 0b e8 f2 b0 93 ff 0f
RSP: 0018:ffffc900009674c0 EFLAGS: 00010246
RAX: ffffffff81d618d9 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc90006b9e000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90000967630 R08: 0000000000000000 R09: 0000000050000028
R10: dffffc0000000000 R11: fffffbfff0e18c4c R12: dffffc0000000000
R13: 0000000000000174 R14: 0000000000000030 R15: 0000000000000000
FS: 00007f722d6366c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b34512ff8 CR3: 000000012fc45000 CR4: 00000000003506b0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
ext4_force_split_extent_at fs/ext4/extents.c:319 [inline]
ext4_ext_remove_space+0x652/0x40d0 fs/ext4/extents.c:2880
ext4_punch_hole+0x77c/0xbd0 fs/ext4/inode.c:4137
ext4_fallocate+0x2b6/0x1de0 fs/ext4/extents.c:4771
vfs_fallocate+0x4b4/0x590 fs/open.c:309
madvise_remove mm/madvise.c:964 [inline]
madvise_vma_behavior mm/madvise.c:988 [inline]
madvise_walk_vmas mm/madvise.c:1218 [inline]
do_madvise+0x1435/0x2420 mm/madvise.c:1396
__do_sys_madvise mm/madvise.c:1409 [inline]
__se_sys_madvise mm/madvise.c:1407 [inline]
__x64_sys_madvise+0xa9/0xc0 mm/madvise.c:1407
x64_sys_call+0x89b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:29
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f722ebdbdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f722d636028 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007f722ee54fa0 RCX: 00007f722ebdbdd9
RDX: 0000000000000009 RSI: 0000000000600003 RDI: 0000200000000000
RBP: 00007f722ec71d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f722ee55038 R14: 00007f722ee54fa0 R15: 00007ffea4bfc848
Modules linked in:
---[ end trace 680bd035519a4854 ]---
RIP: 0010:ext4_split_extent_at+0xe29/0xe50 fs/ext4/extents.c:3189
Code: ff ff 44 89 f1 80 e1 07 fe c1 38 c1 0f 8c fc fb ff ff 4c 89 f7 49 89 d7 e8 64 e4 d2 ff 4c 89 fa e9 e9 fb ff ff e8 07 b1 93 ff <0f> 0b e8 00 b1 93 ff 0f 0b e8 f9 b0 93 ff 0f 0b e8 f2 b0 93 ff 0f
RSP: 0018:ffffc900009674c0 EFLAGS: 00010246
RAX: ffffffff81d618d9 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc90006b9e000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90000967630 R08: 0000000000000000 R09: 0000000050000028
R10: dffffc0000000000 R11: fffffbfff0e18c4c R12: dffffc0000000000
R13: 0000000000000174 R14: 0000000000000030 R15: 0000000000000000
FS: 00007f722d6366c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f539774c000 CR3: 000000012fc45000 CR4: 00000000003506b0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000fffe0ff0 DR7: 0000000000000400