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ext2: merge xattr next entry check to ext2_xattr_entry_valid()

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We have introduced ext2_xattr_entry_valid() for xattr
entry sanity check, so it's better to do relevant things
in one place.

Signed-off-by: Chengguang Xu <cgxu519@zoho.com.cn>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Chengguang Xu 2019-05-28 10:59:45 +08:00 committed by Jan Kara
parent 7f58351a7c
commit 9bb1d7a6bc
1 changed files with 16 additions and 20 deletions
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36
fs/ext2/xattr.c
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@ -145,10 +145,16 @@ ext2_xattr_header_valid(struct ext2_xattr_header *header)
}
static bool
ext2_xattr_entry_valid(struct ext2_xattr_entry *entry, size_t end_offs)
ext2_xattr_entry_valid(struct ext2_xattr_entry *entry,
char *end, size_t end_offs)
{
struct ext2_xattr_entry *next;
size_t size;
next = EXT2_XATTR_NEXT(entry);
if ((char *)next >= end)
return false;
if (entry->e_value_block != 0)
return false;
@ -214,17 +220,14 @@ bad_block:
/* find named attribute */
entry = FIRST_ENTRY(bh);
while (!IS_LAST_ENTRY(entry)) {
struct ext2_xattr_entry *next =
EXT2_XATTR_NEXT(entry);
if ((char *)next >= end)
goto bad_block;
if (!ext2_xattr_entry_valid(entry, inode->i_sb->s_blocksize))
if (!ext2_xattr_entry_valid(entry, end,
inode->i_sb->s_blocksize))
goto bad_block;
if (name_index == entry->e_name_index &&
name_len == entry->e_name_len &&
memcmp(name, entry->e_name, name_len) == 0)
goto found;
entry = next;
entry = EXT2_XATTR_NEXT(entry);
}
if (ext2_xattr_cache_insert(ea_block_cache, bh))
ea_idebug(inode, "cache insert failed");
@ -299,13 +302,10 @@ bad_block:
/* check the on-disk data structure */
entry = FIRST_ENTRY(bh);
while (!IS_LAST_ENTRY(entry)) {
struct ext2_xattr_entry *next = EXT2_XATTR_NEXT(entry);
if ((char *)next >= end)
if (!ext2_xattr_entry_valid(entry, end,
inode->i_sb->s_blocksize))
goto bad_block;
if (!ext2_xattr_entry_valid(entry, inode->i_sb->s_blocksize))
goto bad_block;
entry = next;
entry = EXT2_XATTR_NEXT(entry);
}
if (ext2_xattr_cache_insert(ea_block_cache, bh))
ea_idebug(inode, "cache insert failed");
@ -390,7 +390,7 @@ ext2_xattr_set(struct inode *inode, int name_index, const char *name,
struct super_block *sb = inode->i_sb;
struct buffer_head *bh = NULL;
struct ext2_xattr_header *header = NULL;
struct ext2_xattr_entry *here, *last;
struct ext2_xattr_entry *here = NULL, *last = NULL;
size_t name_len, free, min_offs = sb->s_blocksize;
int not_found = 1, error;
char *end;
@ -444,10 +444,7 @@ bad_block:
*/
last = FIRST_ENTRY(bh);
while (!IS_LAST_ENTRY(last)) {
struct ext2_xattr_entry *next = EXT2_XATTR_NEXT(last);
if ((char *)next >= end)
goto bad_block;
if (!ext2_xattr_entry_valid(last, sb->s_blocksize))
if (!ext2_xattr_entry_valid(last, end, sb->s_blocksize))
goto bad_block;
if (last->e_value_size) {
size_t offs = le16_to_cpu(last->e_value_offs);
@ -465,7 +462,7 @@ bad_block:
if (not_found <= 0)
here = last;
}
last = next;
last = EXT2_XATTR_NEXT(last);
}
if (not_found > 0)
here = last;
@ -476,7 +473,6 @@ bad_block:
/* We will use a new extended attribute block. */
free = sb->s_blocksize -
sizeof(struct ext2_xattr_header) - sizeof(__u32);
here = last = NULL; /* avoid gcc uninitialized warning. */
}
if (not_found) {