xattr in ocfs2 maybe 'non-indexed', which saved with additional space requested. It's better to check if the memory is out of bound before memcmp, although this possibility mainly comes from crafted poisonous images. Link: https://lkml.kernel.org/r/20240520024024.1976129-2-joseph.qi@xxxxxxxxxxxxxxxxx Signed-off-by: Ferry Meng <mengferry@xxxxxxxxxxxxxxxxx> Signed-off-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx> Reported-by: lei lu <llfamsec@xxxxxxxxx> Reviewed-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx> Cc: Changwei Ge <gechangwei@xxxxxxx> Cc: Gang He <ghe@xxxxxxxx> Cc: Joel Becker <jlbec@xxxxxxxxxxxx> Cc: Jun Piao <piaojun@xxxxxxxxxx> Cc: Junxiao Bi <junxiao.bi@xxxxxxxxxx> Cc: Mark Fasheh <mark@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 8aea94c90739..35c0cc2a51af 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -1068,7 +1068,7 @@ static int ocfs2_xattr_find_entry(struct inode *inode, int name_index, { struct ocfs2_xattr_entry *entry; size_t name_len; - int i, cmp = 1; + int i, name_offset, cmp = 1; if (name == NULL) return -EINVAL; @@ -1083,10 +1083,15 @@ static int ocfs2_xattr_find_entry(struct inode *inode, int name_index, cmp = name_index - ocfs2_xattr_get_type(entry); if (!cmp) cmp = name_len - entry->xe_name_len; - if (!cmp) - cmp = memcmp(name, (xs->base + - le16_to_cpu(entry->xe_name_offset)), - name_len); + if (!cmp) { + name_offset = le16_to_cpu(entry->xe_name_offset); + if ((xs->base + name_offset + name_len) > xs->end) { + ocfs2_error(inode->i_sb, + "corrupted xattr entries"); + return -EFSCORRUPTED; + } + cmp = memcmp(name, (xs->base + name_offset), name_len); + } if (cmp == 0) break; entry += 1;
