[yocto] [PATCH] utils.c: close all file descriptors after completing a ptest
Sakib Sajal
sakib.sajal at windriver.com
Fri May 31 09:45:36 PDT 2019
vredir ptest fails since too many file descriptors were open.
>From the failed ptest log:
run-vredir
87,88c87,88
< ./vredir6.sub: line 10: /dev/null: Too many open files
< ./vredir6.sub: line 13: /dev/null: Too many open files
FAIL: run-vredir
Added function to close file descriptors before starting a new process.
Signed-off-by: Sakib Sajal <sakib.sajal at windriver.com>
Signed-off-by: Randy Macleod <randy.macleod at windriver.com>
---
utils.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/utils.c b/utils.c
index 504df0b..05c2bfe 100644
--- a/utils.c
+++ b/utils.c
@@ -28,6 +28,7 @@
#include <fcntl.h>
#include <time.h>
#include <dirent.h>
+#include <sys/resource.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
@@ -240,6 +241,23 @@ filter_ptests(struct ptest_list *head, char **ptests, int ptest_num)
return head_new;
}
+/* Close all fds from 3 up to 'ulimit -n'
+ * i.e. do not close STDIN, STDOUT, STDERR.
+ * Typically called in in a child process after forking
+ * but before exec as a good policy especially for security.
+ */
+static void
+close_fds(void)
+{
+ struct rlimit curr_lim;
+ getrlimit(RLIMIT_NOFILE, &curr_lim);
+
+ int fd;
+ for (fd=3; fd < curr_lim.rlim_cur; fd++) {
+ (void) close(fd);
+ }
+}
+
static inline void
run_child(char *run_ptest, int fd_stdout, int fd_stderr)
{
@@ -252,6 +270,7 @@ run_child(char *run_ptest, int fd_stdout, int fd_stderr)
dup2(fd_stdout, STDOUT_FILENO);
// XXX: Redirect stderr to stdout to avoid buffer ordering problems.
dup2(fd_stdout, STDERR_FILENO);
+ close_fds();
execv(run_ptest, argv);
exit(1);
--
2.20.1
More information about the yocto
mailing list