Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 60c0d361 authored by Ferry Meng's avatar Ferry Meng Committed by Greg Kroah-Hartman
Browse files

ocfs2: add bounds checking to ocfs2_xattr_find_entry() 

[ Upstream commit 9e3041fecdc8f78a5900c3aa51d3d756e73264d6 ]

Add a paranoia check to make sure it doesn't stray beyond valid memory
region containing ocfs2 xattr entries when scanning for a match.  It will
prevent out-of-bound access in case of crafted images.

Link: https://lkml.kernel.org/r/20240520024024.1976129-1-joseph.qi@linux.alibaba.com


Signed-off-by: default avatarFerry Meng <mengferry@linux.alibaba.com>
Signed-off-by: default avatarJoseph Qi <joseph.qi@linux.alibaba.com>
Reported-by: default avatarlei lu <llfamsec@gmail.com>
Reviewed-by: default avatarJoseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Stable-dep-of: af77c4fc1871 ("ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry()")
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
parent 71fbc501

fs/ocfs2/xattr.c

+8 −4
Original line number Diff line number Diff line
@@ -1068,7 +1068,7 @@ ssize_t ocfs2_listxattr(struct dentry *dentry, 
	return i_ret + b_ret;

}



static int ocfs2_xattr_find_entry(int name_index,

static int ocfs2_xattr_find_entry(struct inode *inode, int name_index,

				  const char *name,

				  struct ocfs2_xattr_search *xs)

{
@@ -1082,6 +1082,10 @@ static int ocfs2_xattr_find_entry(int name_index, 
	name_len = strlen(name);

	entry = xs->here;

	for (i = 0; i < le16_to_cpu(xs->header->xh_count); i++) {

		if ((void *)entry >= xs->end) {

			ocfs2_error(inode->i_sb, "corrupted xattr entries");

			return -EFSCORRUPTED;

		}

		cmp = name_index - ocfs2_xattr_get_type(entry);

		if (!cmp)

			cmp = name_len - entry->xe_name_len;
@@ -1172,7 +1176,7 @@ static int ocfs2_xattr_ibody_get(struct inode *inode, 
	xs->base = (void *)xs->header;

	xs->here = xs->header->xh_entries;



	ret = ocfs2_xattr_find_entry(name_index, name, xs);

	ret = ocfs2_xattr_find_entry(inode, name_index, name, xs);

	if (ret)

		return ret;

	size = le64_to_cpu(xs->here->xe_value_size);
@@ -2704,7 +2708,7 @@ static int ocfs2_xattr_ibody_find(struct inode *inode, 


	/* Find the named attribute. */

	if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL) {

		ret = ocfs2_xattr_find_entry(name_index, name, xs);

		ret = ocfs2_xattr_find_entry(inode, name_index, name, xs);

		if (ret && ret != -ENODATA)

			return ret;

		xs->not_found = ret;
@@ -2839,7 +2843,7 @@ static int ocfs2_xattr_block_find(struct inode *inode, 
		xs->end = (void *)(blk_bh->b_data) + blk_bh->b_size;

		xs->here = xs->header->xh_entries;



		ret = ocfs2_xattr_find_entry(name_index, name, xs);

		ret = ocfs2_xattr_find_entry(inode, name_index, name, xs);

	} else

		ret = ocfs2_xattr_index_block_find(inode, blk_bh,

						   name_index,