[PATCH] kernfs: move return value check after kmalloc()

From: Austin Kim
Date: Thu May 20 2021 - 22:55:35 EST


With 414985ae23c0 ("sysfs, kernfs: move file core code to fs/kernfs/file.c"),
'return -ENOMEM' is executed when kmalloc() returns NULL.

Since 'commit 4ef67a8c95f3 ("sysfs/kernfs: make read requests on pre-alloc
files use the buffer.")', 'return -ENOMEM' statement is not properly located.

Fix it by moving 'return -ENOMEM' after return from kmalloc().

Fixes: 4ef67a8c95f3 ("sysfs/kernfs: make read requests on pre-alloc files use the buffer.")
Signed-off-by: Austin Kim <austindh.kim@xxxxxxxxx>
---
fs/kernfs/file.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index c75719312147..c5e2429af836 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -191,10 +191,11 @@ static ssize_t kernfs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
buf = of->prealloc_buf;
if (buf)
mutex_lock(&of->prealloc_mutex);
- else
+ else {
buf = kmalloc(len, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
+ if (!buf)
+ return -ENOMEM;
+ }

/*
* @of->mutex nests outside active ref and is used both to ensure that
--
2.20.1