From: Tycho Andersen <tandersen@xxxxxxxxxxx>
We want to ensure that /proc/self/comm stays useful for execveat() callers.
Signed-off-by: Tycho Andersen <tandersen@xxxxxxxxxxx>
---
tools/testing/selftests/exec/execveat.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)
diff --git a/tools/testing/selftests/exec/execveat.c b/tools/testing/selftests/exec/execveat.c
index 071e03532cba..091029f4ca9b 100644
--- a/tools/testing/selftests/exec/execveat.c
+++ b/tools/testing/selftests/exec/execveat.c
@@ -419,6 +419,9 @@ int main(int argc, char **argv)
if (argc >= 2) {
/* If we are invoked with an argument, don't run tests. */
const char *in_test = getenv("IN_TEST");
+ /* TASK_COMM_LEN == 16 */
+ char buf[32];
+ int fd;
if (verbose) {
ksft_print_msg("invoked with:\n");
@@ -432,6 +435,28 @@ int main(int argc, char **argv)
return 1;
}
+ fd = open("/proc/self/comm", O_RDONLY);
+ if (fd < 0) {
+ perror("open comm");
+ return 1;
+ }
+
+ if (read(fd, buf, sizeof(buf)) < 0) {
+ close(fd);
+ perror("read comm");
+ return 1;
+ }
+ close(fd);
+
+ /*
+ * /proc/self/comm should fail to convert to an integer, i.e.
+ * atoi() should return 0.
+ */
+ if (atoi(buf) != 0) {
+ ksft_print_msg("bad /proc/self/comm: %s", buf);
+ return 1;
+ }
+
/* Use the final argument as an exit code. */
rc = atoi(argv[argc - 1]);
exit(rc);