Do not leak a file descriptor when opening nohup.out. Make sure

that stdout and stderr are not closed.
from Nan Xiao

diff --git a/usr.bin/nohup/nohup.c b/usr.bin/nohup/nohup.c
index d411a0c..6f01691 100644 (file)
--- a/usr.bin/nohup/nohup.c
+++ b/usr.bin/nohup/nohup.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: nohup.c,v 1.17 2018/04/26 12:42:51 guenther Exp $     */
+/*     $OpenBSD: nohup.c,v 1.18 2018/09/14 18:17:46 bluhm Exp $        */
 /*     $NetBSD: nohup.c,v 1.6 1995/08/31 23:35:25 jtc Exp $    */
 
 /*
@@ -78,13 +78,14 @@ main(int argc, char *argv[])
        if (argc < 2)
                usage();
 
-       if (isatty(STDOUT_FILENO))
+       if (isatty(STDOUT_FILENO) || errno == EBADF)
                dofile();
 
        if (pledge("stdio exec", NULL) == -1)
                err(1, "pledge");
 
-       if (isatty(STDERR_FILENO) && dup2(STDOUT_FILENO, STDERR_FILENO) == -1) {
+       if ((isatty(STDERR_FILENO) || errno == EBADF) &&
+           dup2(STDOUT_FILENO, STDERR_FILENO) == -1) {
                /* may have just closed stderr */
                (void)fprintf(stdin, "nohup: %s\n", strerror(errno));
                exit(EXIT_MISC);
@@ -125,6 +126,8 @@ dupit:
        (void)lseek(fd, (off_t)0, SEEK_END);
        if (dup2(fd, STDOUT_FILENO) == -1)
                err(EXIT_MISC, NULL);
+       if (fd > STDERR_FILENO)
+               (void)close(fd);
        (void)fprintf(stderr, "sending output to %s\n", p);
 }