[PATCH] s390/diag324: Preserve -EBUSY return code

Sumanth Korikkar <[email protected]>
Newsgroups org.kernel.vger.linux-s390
Message-ID <[email protected]>
When diag324 reports -EBUSY, the error code is
overwritten by the result of copy_to_user() and put_user(). As a result,
the ioctl may incorrectly return success instead of -EBUSY.

Preserve the original diag324 return code and only return -EFAULT when
copying data to userspace fails.

Fixes: 90e6f191e1ee ("s390/diag324: Retrieve power readings via diag 0x324")
Signed-off-by: Sumanth Korikkar <[email protected]>
---
 arch/s390/kernel/diag/diag324.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/s390/kernel/diag/diag324.c b/arch/s390/kernel/diag/diag324.c
index fe325c2a2d0d..3eec0cc8fb9e 100644
--- a/arch/s390/kernel/diag/diag324.c
+++ b/arch/s390/kernel/diag/diag324.c
@@ -182,8 +182,7 @@ long diag324_pibbuf(unsigned long arg)
 		goto out;
 	rc = copy_to_user((void __user *)address, data->pib, data->pib->len);
 	rc |= put_user(data->sequence, &udata->sequence);
-	if (rc)
-		rc = -EFAULT;
+	rc = rc ? -EFAULT : data->rc;
 out:
 	mutex_unlock(&pibmutex);
 	return rc;
-- 
2.54.0
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.