ceph: avoid panic with mismatched symlink sizes in fill_inode()
Return -EINVAL rather than panic if iinfo->symlink_len and inode->i_size
do not match.
Also use kstrndup rather than kmalloc/memcpy.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Reviewed-by: Alex Elder <elder@dreamhost.com>
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 2c48937..9fff9f3 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -677,18 +677,19 @@
case S_IFLNK:
inode->i_op = &ceph_symlink_iops;
if (!ci->i_symlink) {
- int symlen = iinfo->symlink_len;
+ u32 symlen = iinfo->symlink_len;
char *sym;
- BUG_ON(symlen != inode->i_size);
spin_unlock(&ci->i_ceph_lock);
+ err = -EINVAL;
+ if (WARN_ON(symlen != inode->i_size))
+ goto out;
+
err = -ENOMEM;
- sym = kmalloc(symlen+1, GFP_NOFS);
+ sym = kstrndup(iinfo->symlink, symlen, GFP_NOFS);
if (!sym)
goto out;
- memcpy(sym, iinfo->symlink, symlen);
- sym[symlen] = 0;
spin_lock(&ci->i_ceph_lock);
if (!ci->i_symlink)