diff options
| -rw-r--r-- | conf.c | 4 | ||||
| -rw-r--r-- | isolation.c | 24 |
2 files changed, 12 insertions, 16 deletions
@@ -1177,9 +1177,7 @@ int conf_tap_fd(int argc, char **argv) return -1; p = fdarg; - if (!parse_unsigned(&p, 0, &val) || !parse_eoi(p) || - val > INT_MAX || - (val != STDIN_FILENO && val <= STDERR_FILENO)) + if (!parse_unsigned(&p, 0, &val) || !parse_eoi(p) || val > INT_MAX) die("Invalid --fd: %s", fdarg); return val; diff --git a/isolation.c b/isolation.c index 725a72b..94cbe7f 100644 --- a/isolation.c +++ b/isolation.c @@ -248,7 +248,6 @@ void isolate_initial(void) drop_caps_ep_except(keep); } - /* * isolate_fds() - Close leaked files, but not --fd, stdin, stdout, stderr * @argc: Argument count @@ -256,27 +255,26 @@ void isolate_initial(void) * * Should: * - close all open files except for standard streams and the one from --fd + * - move the --fd descriptor out of the range 0-2 * - * Return: fd number from --fd, or -1 if not specified + * Return: new fd number for descriptor from --fd, or -1 if not specified */ int isolate_fds(int argc, char **argv) { - int fd, rc; + int fd, close_from = STDERR_FILENO + 1; fd = conf_tap_fd(argc, argv); - if (fd == -1) { - rc = close_range(STDERR_FILENO + 1, ~0U, CLOSE_RANGE_UNSHARE); - } else if (fd == STDERR_FILENO + 1) { /* Still a single range */ - rc = close_range(STDERR_FILENO + 2, ~0U, CLOSE_RANGE_UNSHARE); - } else { - rc = close_range(STDERR_FILENO + 1, fd - 1, - CLOSE_RANGE_UNSHARE); - if (!rc) - rc = close_range(fd + 1, ~0U, CLOSE_RANGE_UNSHARE); + if (fd >= 0) { + /* Move the passed fd to a more convenient location */ + if (fd != close_from && + (dup2(fd, close_from) != close_from || + close(fd))) + die_perror("Could not move --fd descriptor"); + fd = close_from++; } - if (rc) { + if (close_range(close_from, ~0U, CLOSE_RANGE_UNSHARE)) { if (errno == ENOSYS || errno == EINVAL) { /* This probably means close_range() or the * CLOSE_RANGE_UNSHARE flag is not supported by the |