From 85563b7fc7ec2cd21e38debb9b28db342e2e8e7c Mon Sep 17 00:00:00 2001 From: Michael Biebl Date: Sun, 21 Apr 2019 21:09:51 +0200 Subject: New upstream version 1.18.0 --- shared/systemd/src/basic/fd-util.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'shared/systemd/src/basic/fd-util.c') diff --git a/shared/systemd/src/basic/fd-util.c b/shared/systemd/src/basic/fd-util.c index 0cc0c6b5..941053bf 100644 --- a/shared/systemd/src/basic/fd-util.c +++ b/shared/systemd/src/basic/fd-util.c @@ -27,6 +27,10 @@ #include "util.h" #include "tmpfile-util.h" +/* The maximum number of iterations in the loop to close descriptors in the fallback case + * when /proc/self/fd/ is inaccessible. */ +#define MAX_FD_LOOP_LIMIT (1024*1024) + int close_nointr(int fd) { assert(fd >= 0); @@ -231,6 +235,13 @@ int close_all_fds(const int except[], size_t n_except) { if (max_fd < 0) return max_fd; + /* Refuse to do the loop over more too many elements. It's better to fail immediately than to + * spin the CPU for a long time. */ + if (max_fd > MAX_FD_LOOP_LIMIT) + return log_debug_errno(SYNTHETIC_ERRNO(EPERM), + "/proc/self/fd is inaccessible. Refusing to loop over %d potential fds.", + max_fd); + for (fd = 3; fd >= 0; fd = fd < max_fd ? fd + 1 : -1) { int q; -- cgit 1.3.0-6-gf8a5