[PATCH 5.14 091/100] nvmet: fixup buffer overrun in nvmet_subsys_attr_serial()

[Greg Kroah-Hartman]

From: Hannes Reinecke <hare@xxxxxxx>

[ Upstream commit f04064814c2a15c22ed9c803f9b634ef34f91092 ]

The serial number is copied into the buffer via memcpy_and_pad()
with the length NVMET_SN_MAX_SIZE. So when printing out we also
need to take just that length as anything beyond that will be
uninitialized.

Signed-off-by: Hannes Reinecke <hare@xxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/nvme/target/configfs.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
index 273555127188..fa88bf9cba4d 100644
--- a/drivers/nvme/target/configfs.c
+++ b/drivers/nvme/target/configfs.c
@@ -1067,7 +1067,8 @@ static ssize_t nvmet_subsys_attr_serial_show(struct config_item *item,
 {
 	struct nvmet_subsys *subsys = to_subsys(item);
 
-	return snprintf(page, PAGE_SIZE, "%s\n", subsys->serial);
+	return snprintf(page, PAGE_SIZE, "%*s\n",
+			NVMET_SN_MAX_SIZE, subsys->serial);
 }
 
 static ssize_t
-- 
2.33.0