From af77c4fc1871847b528d58b7fdafb4aa1f6a9262 Mon Sep 17 00:00:00 2001 From: Ferry Meng Date: Mon, 20 May 2024 10:40:24 +0800 Subject: ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry() 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@linux.alibaba.com Signed-off-by: Ferry Meng Signed-off-by: Joseph Qi Reported-by: lei lu Reviewed-by: Joseph Qi Cc: Changwei Ge Cc: Gang He Cc: Joel Becker Cc: Jun Piao Cc: Junxiao Bi Cc: Mark Fasheh Signed-off-by: Andrew Morton --- fs/ocfs2/xattr.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'fs/ocfs2') 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; -- cgit v1.2.3