From: ZhangPeng <zhangpeng362@huawei.com>
Date: Mon, 4 Nov 2024 12:34:40 +0000 (+0800)
Subject: hostfs: Fix the NULL vs IS_ERR() bug for __filemap_get_folio()
X-Git-Tag: v6.12.2~40
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f888356886be46922dba737d65087df607bd1a46;p=thirdparty%2Fkernel%2Fstable.git

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

[ Upstream commit bed2cc482600296fe04edbc38005ba2851449c10 ]

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>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index 6d1cf2436ead6..084f6ed2dd7a6 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;
 }