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 <[email protected]> Reviewed-by: Alex Elder <[email protected]>
erimatnor · Mar 22, 2012 · 810339e · 810339e
1 parent a661fc5
commit 810339e
Showing 1 changed file with 6 additions and 5 deletions.
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
@@ -677,18 +677,19 @@ static int fill_inode(struct inode *inode,
 	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)