mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

selftests/net: mptcp: fix uninitialized variable warnings 

Same init_rng() in both tests. The function reads /dev/urandom to
initialize srand(). In case of failure, it falls back onto the
entropy in the uninitialized variable. Not sure if this is on purpose.
But failure reading urandom should be rare, so just fail hard. While
at it, convert to getrandom(). Which man 4 random suggests is simpler
and more robust.

    mptcp_inq.c:525:6:
    mptcp_connect.c:1131:6:

    error: variable 'foo' is used uninitialized
    whenever 'if' condition is false
    [-Werror,-Wsometimes-uninitialized]

Fixes: 048d19d444 ("mptcp: add basic kselftest for mptcp")
Fixes: b51880568f ("selftests: mptcp: add inq test case")
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: Willem de Bruijn <willemb@google.com>

----

When input is randomized because this is expected to meaningfully
explore edge cases, should we also add
1. logging the random seed to stdout and
2. adding a command line argument to replay from a specific seed
I can do this in net-next, if authors find it useful in this case.
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>

Link: https://lore.kernel.org/r/20231124171645.1011043-5-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Willem de Bruijn 2023-11-24 12:15:22 -05:00 committed by Jakub Kicinski
parent 59fef379d4
commit 00a4f8fd9c
2 changed files with 8 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
tools/testing/selftests/net/mptcp/mptcp_connect.c
View File

@ -18,6 +18,7 @@
#include <sys/ioctl.h>
#include <sys/poll.h>
#include <sys/random.h>
#include <sys/sendfile.h>
#include <sys/stat.h>
#include <sys/socket.h>
@ -1125,15 +1126,11 @@ again:
static void init_rng(void)
{
int fd = open("/dev/urandom", O_RDONLY);
unsigned int foo;
if (fd > 0) {
int ret = read(fd, &foo, sizeof(foo));
if (ret < 0)
srand(fd + foo);
close(fd);
if (getrandom(&foo, sizeof(foo), 0) == -1) {
perror("getrandom");
exit(1);
}
srand(foo);

11
tools/testing/selftests/net/mptcp/mptcp_inq.c
View File

@ -18,6 +18,7 @@
#include <time.h>
#include <sys/ioctl.h>
#include <sys/random.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/wait.h>
@ -519,15 +520,11 @@ static int client(int unixfd)
static void init_rng(void)
{
int fd = open("/dev/urandom", O_RDONLY);
unsigned int foo;
if (fd > 0) {
int ret = read(fd, &foo, sizeof(foo));
if (ret < 0)
srand(fd + foo);
close(fd);
if (getrandom(&foo, sizeof(foo), 0) == -1) {
perror("getrandom");
exit(1);
}
srand(foo);