[PATCH v4 0/2] ext4: fix WARNING in ext4_update_inline_data

[PATCH v4 0/2] ext4: fix WARNING in ext4_update_inline_data

[Ye Bin]

From: Ye Bin <yebin10@huawei.com>

Diff v4 vs v3:
Change the first patch's changelog.

Diff v3 vs v2:
Remove set 'EXT4_STATE_MAY_INLINE_DATA' flag from ext4_find_inline_data_nolock()

Diff v2 vs v1:
Only update 'inline_off' when do extra expand.

Ye Bin (2):
  ext4: remove set 'EXT4_STATE_MAY_INLINE_DATA' flag from
    ext4_find_inline_data_nolock()
  ext4: fix WARNING in ext4_update_inline_data

 fs/ext4/inline.c | 1 -
 fs/ext4/inode.c  | 7 ++++++-
 fs/ext4/xattr.c  | 3 +++
 3 files changed, 9 insertions(+), 2 deletions(-)

-- 
2.31.1

[PATCH v4 1/2] ext4: remove set 'EXT4_STATE_MAY_INLINE_DATA' flag from ext4_find_inline_data_nolock()

[Ye Bin]

From: Ye Bin <yebin10@huawei.com>

The only caller of ext4_find_inline_data_nolock() that needs setting of
EXT4_STATE_MAY_INLINE_DATA flag is ext4_iget_extra_inode(). In
ext4_write_inline_data_end() we just need to update inode->i_inline_off.
Since we are going to add one more caller that does not need to set
EXT4_STATE_MAY_INLINE_DATA, just move setting of EXT4_STATE_MAY_INLINE_DATA
out to ext4_iget_extra_inode().

Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 fs/ext4/inline.c | 1 -
 fs/ext4/inode.c  | 7 ++++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index 2b42ececa46d..1602d74b5eeb 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -159,7 +159,6 @@ int ext4_find_inline_data_nolock(struct inode *inode)
 					(void *)ext4_raw_inode(&is.iloc));
 		EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
 				le32_to_cpu(is.s.here->e_value_size);
-		ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
 	}
 out:
 	brelse(is.iloc.bh);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index d251d705c276..bf0b7dea4900 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4797,8 +4797,13 @@ static inline int ext4_iget_extra_inode(struct inode *inode,
 
 	if (EXT4_INODE_HAS_XATTR_SPACE(inode)  &&
 	    *magic == cpu_to_le32(EXT4_XATTR_MAGIC)) {
+		int err;
+
 		ext4_set_inode_state(inode, EXT4_STATE_XATTR);
-		return ext4_find_inline_data_nolock(inode);
+		err = ext4_find_inline_data_nolock(inode);
+		if (!err && ext4_has_inline_data(inode))
+			ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+		return err;
 	} else
 		EXT4_I(inode)->i_inline_off = 0;
 	return 0;
-- 
2.31.1

[PATCH v4 2/2] ext4: fix WARNING in ext4_update_inline_data

[Ye Bin]

From: Ye Bin <yebin10@huawei.com>

Syzbot found the following issue:
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 without journal. Quota mode: none.
fscrypt: AES-256-CTS-CBC using implementation "cts-cbc-aes-aesni"
fscrypt: AES-256-XTS using implementation "xts-aes-aesni"
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5071 at mm/page_alloc.c:5525 __alloc_pages+0x30a/0x560 mm/page_alloc.c:5525
Modules linked in:
CPU: 1 PID: 5071 Comm: syz-executor263 Not tainted 6.2.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:__alloc_pages+0x30a/0x560 mm/page_alloc.c:5525
RSP: 0018:ffffc90003c2f1c0 EFLAGS: 00010246
RAX: ffffc90003c2f220 RBX: 0000000000000014 RCX: 0000000000000000
RDX: 0000000000000028 RSI: 0000000000000000 RDI: ffffc90003c2f248
RBP: ffffc90003c2f2d8 R08: dffffc0000000000 R09: ffffc90003c2f220
R10: fffff52000785e49 R11: 1ffff92000785e44 R12: 0000000000040d40
R13: 1ffff92000785e40 R14: dffffc0000000000 R15: 1ffff92000785e3c
FS:  0000555556c0d300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f95d5e04138 CR3: 00000000793aa000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 alloc_pages_node include/linux/gfp.h:260 [inline]
 __kmalloc_large_node+0x95/0x1e0 mm/slab_common.c:1113
 __do_kmalloc_node mm/slab_common.c:956 [inline]
 __kmalloc+0xfe/0x190 mm/slab_common.c:981
 kmalloc include/linux/slab.h:584 [inline]
 kzalloc include/linux/slab.h:720 [inline]
 ext4_update_inline_data+0x236/0x6b0 fs/ext4/inline.c:346
 ext4_update_inline_dir fs/ext4/inline.c:1115 [inline]
 ext4_try_add_inline_entry+0x328/0x990 fs/ext4/inline.c:1307
 ext4_add_entry+0x5a4/0xeb0 fs/ext4/namei.c:2385
 ext4_add_nondir+0x96/0x260 fs/ext4/namei.c:2772
 ext4_create+0x36c/0x560 fs/ext4/namei.c:2817
 lookup_open fs/namei.c:3413 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0x12ac/0x2dd0 fs/namei.c:3711
 do_filp_open+0x264/0x4f0 fs/namei.c:3741
 do_sys_openat2+0x124/0x4e0 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_openat fs/open.c:1342 [inline]
 __se_sys_openat fs/open.c:1337 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1337
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Above issue happens as follows:
ext4_iget
   ext4_find_inline_data_nolock ->i_inline_off=164 i_inline_size=60
ext4_try_add_inline_entry
   __ext4_mark_inode_dirty
      ext4_expand_extra_isize_ea ->i_extra_isize=32 s_want_extra_isize=44
         ext4_xattr_shift_entries
	 ->after shift i_inline_off is incorrect, actually is change to 176
ext4_try_add_inline_entry
  ext4_update_inline_dir
    get_max_inline_xattr_value_size
      if (EXT4_I(inode)->i_inline_off)
	entry = (struct ext4_xattr_entry *)((void *)raw_inode +
			EXT4_I(inode)->i_inline_off);
        free += EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size));
	->As entry is incorrect, then 'free' may be negative
   ext4_update_inline_data
      value = kzalloc(len, GFP_NOFS);
      -> len is unsigned int, maybe very large, then trigger warning when
         'kzalloc()'
To resolve above issue there's need to update 'i_inline_off' after
'ext4_xattr_shift_entries()'. At here we do not need to set
EXT4_STATE_MAY_INLINE_DATA flag. As if do mark inode dirty we already set
this flag if need. If we set EXT4_STATE_MAY_INLINE_DATA flag may lead to
BUG_ON in ext4_writepages().

Reported-by: syzbot+d30838395804afc2fa6f@syzkaller.appspotmail.com
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 fs/ext4/xattr.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 62f2ec599218..767454d74cd6 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -2852,6 +2852,9 @@ int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
 			(void *)header, total_ino);
 	EXT4_I(inode)->i_extra_isize = new_extra_isize;
 
+	if (ext4_has_inline_data(inode))
+		error = ext4_find_inline_data_nolock(inode);
+
 cleanup:
 	if (error && (mnt_count != le16_to_cpu(sbi->s_es->s_mnt_count))) {
 		ext4_warning(inode->i_sb, "Unable to expand inode %lu. Delete some EAs or run e2fsck.",
-- 
2.31.1