Hi Greg,
The problem had been fixed by 764a5c6b1fa4 ("xattr handlers: Simplify list operation") in v4.5-rc1, but the modification in that commit may be too much because it modifies all file-systems which implement xattr, so I create a single patch for jffs2 to fix the problem. Which one is your preference ?
Hi Andreas,
Could you please help review the patch ?
Thanks, Tao ---
From: Hou Tao houtao1@huawei.com
When a file have multiple xattrs and the passed buffer is smaller than the required size, jffs2_listxattr() should return -ERANGE instead of continue, else Oops may occurs due to memory corruption.
Also remove the unnecessary check ("rc < 0"), because xhandle->list(...) will not return an error number.
Spotted by generic/377 in xfstests-dev.
Signed-off-by: Hou Tao houtao1@huawei.com --- fs/jffs2/xattr.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/jffs2/xattr.c b/fs/jffs2/xattr.c index 4c2c03663533..8e1427762eeb 100644 --- a/fs/jffs2/xattr.c +++ b/fs/jffs2/xattr.c @@ -1004,12 +1004,14 @@ ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size) rc = xhandle->list(xhandle, dentry, buffer + len, size - len, xd->xname, xd->name_len); + if (rc > size - len) { + rc = -ERANGE; + goto out; + } } else { rc = xhandle->list(xhandle, dentry, NULL, 0, xd->xname, xd->name_len); } - if (rc < 0) - goto out; len += rc; } rc = len; --