seqfile: fix uninitialized memory allocation in mounts_open()

proc_mounts.m.buf is not explicitly zeroed at allocation time, which may later confuse the seqfile code and triggle an kfree(m->buf).

fs/proc/base.c +1 -1

@@ -380,7 +380,7 @@ static int mounts_open(struct inode *ino
 
 	if (ns) {
 		ret = -ENOMEM;
-		p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
+		p = kzalloc(sizeof(struct proc_mounts), GFP_KERNEL);
 		if (p) {
 			file->private_data = &p->m;
 			ret = seq_open(file, &mounts_op);

Quoted 2 lines · Fengguang Wu

proc_mounts.m.buf is not explicitly zeroed at allocation time, which may later confuse the seqfile code and triggle an kfree(m->buf).

It's cleared in seq_open().

Quoted 11 lines

fs/proc/base.c +1 -1

@@ -380,7 +380,7 @@ static int mounts_open(struct inode *ino
 
 	if (ns) {
 		ret = -ENOMEM;
-		p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
+		p = kzalloc(sizeof(struct proc_mounts), GFP_KERNEL);
 		if (p) {
 			file->private_data = &p->m;
 			ret = seq_open(file, &mounts_op);