fs/orangefs: use snprintf() instead of sprintf()

[ Upstream commit cdfa1304657d6f23be8fd2bb0516380a3c89034e ]

sprintf() is discouraged for use with bounded destination buffers
as it does not prevent buffer overflows when the formatted output
exceeds the destination buffer size. snprintf() is a safer
alternative as it limits the number of bytes written and ensures
NUL-termination.

Replace sprintf() with snprintf() for copying the debug string
into a temporary buffer, using ORANGEFS_MAX_DEBUG_STRING_LEN as
the maximum size to ensure safe formatting and prevent memory
corruption in edge cases.

EDIT: After this patch sat on linux-next for a few days, Dan
Carpenter saw it and suggested that I use scnprintf instead of
snprintf. I made the change and retested.

Signed-off-by: Amir Mohammad Jahangirzad <a.jahangirzad@gmail.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/orangefs/orangefs-debugfs.c b/fs/orangefs/orangefs-debugfs.c
index e8e3badbc2ec0693aea07f1b8071e02f8ea9817b..1c375fb650185c691d21ae3cfa5617f9f32d67e2 100644 (file)
--- a/fs/orangefs/orangefs-debugfs.c
+++ b/fs/orangefs/orangefs-debugfs.c
@@ -396,7 +396,7 @@ static ssize_t orangefs_debug_read(struct file *file,
                goto out;
 
        mutex_lock(&orangefs_debug_lock);
-       sprintf_ret = sprintf(buf, "%s", (char *)file->private_data);
+       sprintf_ret = scnprintf(buf, ORANGEFS_MAX_DEBUG_STRING_LEN, "%s", (char *)file->private_data);
        mutex_unlock(&orangefs_debug_lock);
 
        read_ret = simple_read_from_buffer(ubuf, count, ppos, buf, sprintf_ret);