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Date:   Thu, 25 Aug 2022 16:36:20 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     JeffleXu <jefflexu@linux.alibaba.com>
Cc:     David Howells <dhowells@redhat.com>, Sun Ke <sunke32@huawei.com>,
        linux-cachefs@redhat.com, linux-kernel@vger.kernel.org,
        kernel-janitors@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v3] cachefiles: fix error return code in
 cachefiles_ondemand_copen()
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I spent a long time looking at this as well...  It's really inscrutable
code.  It would be more readable if we just spelled things out in the
most pedantic way possible:

diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c
index 1fee702d5529..7e1586bd5cf3 100644
--- a/fs/cachefiles/ondemand.c
+++ b/fs/cachefiles/ondemand.c
@@ -158,9 +158,13 @@ int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args)
 
 	/* fail OPEN request if daemon reports an error */
 	if (size < 0) {
-		if (!IS_ERR_VALUE(size))
-			size = -EINVAL;
-		req->error = size;
+		if (!IS_ERR_VALUE(size)) {
+			req->error = -EINVAL;
+			ret = -EINVAL;
+		} else {
+			req->error = size;
+			ret = 0;
+		}
 		goto out;
 	}