[NET]: Fix net/socket.c warnings.

GCC (correctly) says:

net/socket.c: In function ‘sys_sendto’:
net/socket.c:1510: warning: ‘err’ may be used uninitialized in this function
net/socket.c: In function ‘sys_recvfrom’:
net/socket.c:1571: warning: ‘err’ may be used uninitialized in this function

sock_from_file() either returns filp->private_data or it
sets *err and returns NULL.

Callers return "err" on NULL, but filp->private_data could
be NULL.

Some minor rearrangements of error handling in sys_sendto
and sys_recvfrom solves the issue.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/socket.c b/net/socket.c
index fc74930f1443b659b082bcf53c99042c1548ea10..5f374e1ff5268922371fa6c485f63a5ae2089ba6 100644 (file)
--- a/net/socket.c
+++ b/net/socket.c
@@ -1514,8 +1514,9 @@ asmlinkage long sys_sendto(int fd, void __user *buff, size_t len,
        struct file *sock_file;
 
        sock_file = fget_light(fd, &fput_needed);
+       err = -EBADF;
        if (!sock_file)
-               return -EBADF;
+               goto out;
 
        sock = sock_from_file(sock_file, &err);
        if (!sock)
@@ -1542,6 +1543,7 @@ asmlinkage long sys_sendto(int fd, void __user *buff, size_t len,
 
 out_put:
        fput_light(sock_file, fput_needed);
+out:
        return err;
 }
 
@@ -1573,12 +1575,13 @@ asmlinkage long sys_recvfrom(int fd, void __user *ubuf, size_t size,
        int fput_needed;
 
        sock_file = fget_light(fd, &fput_needed);
+       err = -EBADF;
        if (!sock_file)
-               return -EBADF;
+               goto out;
 
        sock = sock_from_file(sock_file, &err);
        if (!sock)
-               goto out;
+               goto out_put;
 
        msg.msg_control = NULL;
        msg.msg_controllen = 0;
@@ -1597,8 +1600,9 @@ asmlinkage long sys_recvfrom(int fd, void __user *ubuf, size_t size,
                if (err2 < 0)
                        err = err2;
        }
-out:
+out_put:
        fput_light(sock_file, fput_needed);
+out:
        return err;
 }