diff mbox series

hostfs: Fix the NULL vs IS_ERR() bug for __filemap_get_folio()

Message ID 20241104123440.1347175-1-zhangpeng362@huawei.com
State New
Headers show
Series hostfs: Fix the NULL vs IS_ERR() bug for __filemap_get_folio() | expand

Commit Message

Peng Zhang Nov. 4, 2024, 12:34 p.m. UTC 
From: ZhangPeng <zhangpeng362@huawei.com>

The __filemap_get_folio() function returns error pointers.
It never returns NULL. So use IS_ERR() to check it.

Fixes: 1da86618bdce ("fs: Convert aops->write_begin to take a folio")
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
---
 fs/hostfs/hostfs_kern.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Johannes Berg Nov. 8, 2024, 9:17 a.m. UTC | #1 
On Mon, 2024-11-04 at 20:34 +0800, Peng Zhang wrote:
> From: ZhangPeng <zhangpeng362@huawei.com>
> 
> The __filemap_get_folio() function returns error pointers.
> It never returns NULL. So use IS_ERR() to check it.
> 
> Fixes: 1da86618bdce ("fs: Convert aops->write_begin to take a folio")
> Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>

Not sure it's critical, but for um I wasn't planning to send a pull
request for 6.12-rc (and I suspect Richard also wasn't, as there are no
other fixes). Also, the original commit went through another tree.

Christian what do you think? Do you want to pick it up? Or should we
pick it up via um, but then likely only for 6.13?

If you could pick it up:
Acked-by: Johannes Berg <johannes@sipsolutions.net>

johannes
diff mbox series

Patch

diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index 6d1cf2436ead..084f6ed2dd7a 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -471,8 +471,8 @@  static int hostfs_write_begin(struct file *file, struct address_space *mapping,
 
 	*foliop = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
 			mapping_gfp_mask(mapping));
-	if (!*foliop)
-		return -ENOMEM;
+	if (IS_ERR(*foliop))
+		return PTR_ERR(*foliop);
 	return 0;
 }