[PATCH] fs:cifs: convert from atomic_t to refcount_t on tlink->tl_count

From: cgel . zte
Date: Fri Nov 12 2021 - 04:31:00 EST


From: chiminghao <chi.minghao@xxxxxxxxxx>

use refcount_t instead of atomic_t
which prevents reference counter overflows.

Reported-by: Zeal Robot <zealci@xxxxxxxxxx>
Signed-off-by: chiminghao <chi.minghao@xxxxxxxxxx>
---
fs/cifs/cifsglob.h | 4 ++--
fs/cifs/connect.c | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 41e97df4e0e5..a8edaada0fea 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -8,7 +8,7 @@
*/
#ifndef _CIFS_GLOB_H
#define _CIFS_GLOB_H
-
+#include <linux/refcount.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/inet.h>
@@ -1115,7 +1115,7 @@ struct tcon_link {
#define TCON_LINK_PENDING 1
#define TCON_LINK_IN_TREE 2
unsigned long tl_time;
- atomic_t tl_count;
+ refcount_t tl_count;
struct cifs_tcon *tl_tcon;
};

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 9637465d23db..4aad8c9acf2e 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2318,7 +2318,7 @@ cifs_put_tlink(struct tcon_link *tlink)
if (!tlink || IS_ERR(tlink))
return;

- if (!atomic_dec_and_test(&tlink->tl_count) ||
+ if (!refcount_dec_and_test(&tlink->tl_count) ||
test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
tlink->tl_time = jiffies;
return;
--
2.25.1