Ferry Meng (2): ocfs2: add bounds checking to ocfs2_xattr_find_entry() ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry()
fs/ocfs2/xattr.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-)
From: Ferry Meng mengferry@linux.alibaba.com
mainline inclusion from mainline-v6.11-rc1 commit 9e3041fecdc8f78a5900c3aa51d3d756e73264d6 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAG8SI CVE: CVE-2024-41016
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
--------------------------------
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.c... Signed-off-by: Ferry Meng mengferry@linux.alibaba.com Signed-off-by: Joseph Qi joseph.qi@linux.alibaba.com Reported-by: lei lu llfamsec@gmail.com Reviewed-by: Joseph 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: Andrew Morton akpm@linux-foundation.org Signed-off-by: Yu Liao liaoyu15@huawei.com --- fs/ocfs2/xattr.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index b562cfef888a..e6220f7f7cf3 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -1062,7 +1062,7 @@ 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) { @@ -1076,6 +1076,10 @@ 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; @@ -1166,7 +1170,7 @@ 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); @@ -2698,7 +2702,7 @@ 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; @@ -2833,7 +2837,7 @@ 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,
From: Ferry Meng mengferry@linux.alibaba.com
mainline inclusion from mainline-v6.11-rc1 commit af77c4fc1871847b528d58b7fdafb4aa1f6a9262 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAG8SI CVE: CVE-2024-41016
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
--------------------------------
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.c... Signed-off-by: Ferry Meng mengferry@linux.alibaba.com Signed-off-by: Joseph Qi joseph.qi@linux.alibaba.com Reported-by: lei lu llfamsec@gmail.com Reviewed-by: Joseph Qi joseph.qi@linux.alibaba.com Cc: Changwei Ge gechangwei@live.cn Cc: Gang He ghe@suse.com Cc: Joel Becker jlbec@evilplan.org Cc: Jun Piao piaojun@huawei.com Cc: Junxiao Bi junxiao.bi@oracle.com Cc: Mark Fasheh mark@fasheh.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Yu Liao liaoyu15@huawei.com --- fs/ocfs2/xattr.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index e6220f7f7cf3..29d53d1d1476 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;
反馈： 您发送到kernel@openeuler.org的补丁/补丁集，已成功转换为PR！ PR链接地址： https://gitee.com/openeuler/kernel/pulls/10762 邮件列表地址：https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/B...
FeedBack: The patch(es) which you have sent to kernel@openeuler.org mailing list has been converted to a pull request successfully! Pull request link: https://gitee.com/openeuler/kernel/pulls/10762 Mailing list address: https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/B...
-
patchwork bot -
Yu Liao