From: Dan Carpenter dan.carpenter@oracle.com
[ Upstream commit 5ffa828534036348fa90fb3079ccc0972d202c4a ]
The intent here was to return negative error codes but it actually returns positive values. The problem is that type promotion with ternary operations is quite complicated.
"ret" is an int. "copied" is a u32. And the snoop_file_read() function returns long. What happens is that "ret" is cast to u32 and becomes positive then it's cast to long and it's still positive.
Fix this by removing the ternary so that "ret" is type promoted directly to long.
Fixes: 3772e5da4454 ("drivers/misc: Aspeed LPC snoop output using misc chardev") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Joel Stanley joel@jms.id.au Reviewed-by: Patrick Venture venture@google.com Link: https://lore.kernel.org/r/YIE90PSXsMTa2Y8n@mwanda Link: https://lore.kernel.org/r/20210423000919.1249474-1-joel@jms.id.au' Signed-off-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/soc/aspeed/aspeed-lpc-snoop.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/soc/aspeed/aspeed-lpc-snoop.c b/drivers/soc/aspeed/aspeed-lpc-snoop.c index dbe5325a324d..538d7aab8db5 100644 --- a/drivers/soc/aspeed/aspeed-lpc-snoop.c +++ b/drivers/soc/aspeed/aspeed-lpc-snoop.c @@ -95,8 +95,10 @@ static ssize_t snoop_file_read(struct file *file, char __user *buffer, return -EINTR; } ret = kfifo_to_user(&chan->fifo, buffer, count, &copied); + if (ret) + return ret;
- return ret ? ret : copied; + return copied; }
static __poll_t snoop_file_poll(struct file *file,