From: Tycho Andersen tandersen@netflix.com
We want to ensure that /proc/self/comm stays useful for execveat() callers.
Signed-off-by: Tycho Andersen tandersen@netflix.com --- 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);