audit: fix signedness bug in audit_log_execve_info()

In the loop, a size_t "len" is used to hold the return value of
audit_log_single_execve_arg(), which returns -1 on error.  In that
case the error handling (len <= 0) will be bypassed since "len" is
unsigned, and the loop continues with (p += len) being wrapped.
Change the type of "len" to signed int to fix the error handling.

	size_t len;
	...
	for (...) {
		len = audit_log_single_execve_arg(...);
		if (len <= 0)
			break;
		p += len;
	}

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Eric Paris <eparis@redhat.com>

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 593237e..86584ec 100644 (file)
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1362,8 +1362,8 @@ static void audit_log_execve_info(struct audit_context *context,
                                  struct audit_buffer **ab,
                                  struct audit_aux_data_execve *axi)
 {
-       int i;
-       size_t len, len_sent = 0;
+       int i, len;
+       size_t len_sent = 0;
        const char __user *p;
        char *buf;