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| author |   Baokun Li <libaokun1@huawei.com> | 2022-06-16 10:13:55 +0800 |
|---|---|---|
| committer |   Theodore Ts'o <tytso@mit.edu> | 2022-08-02 23:52:34 -0400 |
| commit | 179b14152dcb6a24c3415200603aebca70ff13af (patch) | |
| tree | d74747fc80cf2dd18a762c65e2300d0b9377149a /fs | |
| parent | ext4: fix extent status tree race in writeback error recovery path (diff) | |
| download | linux-dev-179b14152dcb6a24c3415200603aebca70ff13af.tar.xz linux-dev-179b14152dcb6a24c3415200603aebca70ff13af.zip | |
ext4: add EXT4_INODE_HAS_XATTR_SPACE macro in xattr.h
When adding an xattr to an inode, we must ensure that the inode_size is
not less than EXT4_GOOD_OLD_INODE_SIZE + extra_isize + pad. Otherwise,
the end position may be greater than the start position, resulting in UAF.
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20220616021358.2504451-2-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/xattr.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h index 77efb9a627ad..f885f362add4 100644 --- a/fs/ext4/xattr.h +++ b/fs/ext4/xattr.h @@ -95,6 +95,19 @@ struct ext4_xattr_entry { #define EXT4_ZERO_XATTR_VALUE ((void *)-1) +/* + * If we want to add an xattr to the inode, we should make sure that + * i_extra_isize is not 0 and that the inode size is not less than + * EXT4_GOOD_OLD_INODE_SIZE + extra_isize + pad. + * EXT4_GOOD_OLD_INODE_SIZE extra_isize header entry pad data + * |--------------------------|------------|------|---------|---|-------| + */ +#define EXT4_INODE_HAS_XATTR_SPACE(inode) \ + ((EXT4_I(inode)->i_extra_isize != 0) && \ + (EXT4_GOOD_OLD_INODE_SIZE + EXT4_I(inode)->i_extra_isize + \ + sizeof(struct ext4_xattr_ibody_header) + EXT4_XATTR_PAD <= \ + EXT4_INODE_SIZE((inode)->i_sb))) + struct ext4_xattr_info { const char *name; const void *value; |