From 9886566abb375043740167ce5066f1a186c71176 Mon Sep 17 00:00:00 2001 From: Andrew Gregory Date: Wed, 3 Oct 2018 00:42:38 -0700 Subject: reset signal handlers before running scripts/hooks Front-ends or libraries may set signals to be ignored, which gets inherited across fork and exec. This can cause scripts to malfunction if they expect the signal. To make matters worse, scripts written in bash can't reset signals that were ignored when bash was started. Fixes FS#56756 Signed-off-by: Andrew Gregory Signed-off-by: Allan McRae --- lib/libalpm/util.c | 20 ++++++++++++++++++++ test/pacman/tests/TESTS | 1 + test/pacman/tests/scriptlet-signal-reset.py | 11 +++++++++++ 3 files changed, 32 insertions(+) create mode 100644 test/pacman/tests/scriptlet-signal-reset.py diff --git a/lib/libalpm/util.c b/lib/libalpm/util.c index a06f5bfd..eaf85e93 100644 --- a/lib/libalpm/util.c +++ b/lib/libalpm/util.c @@ -548,6 +548,25 @@ static int _alpm_chroot_read_from_child(alpm_handle_t *handle, int fd, return 0; } +static void _alpm_reset_signals(void) +{ + /* reset POSIX defined signals (see signal.h) */ + /* there are likely more but there is no easy way + * to get the full list of valid signals */ + int *i, signals[] = { + SIGABRT, SIGALRM, SIGBUS, SIGCHLD, SIGCONT, SIGFPE, SIGHUP, SIGILL, + SIGINT, SIGKILL, SIGPIPE, SIGQUIT, SIGSEGV, SIGSTOP, SIGTERM, SIGTSTP, + SIGTTIN, SIGTTOU, SIGUSR1, SIGUSR2, SIGPOLL, SIGPROF, SIGSYS, SIGTRAP, + SIGURG, SIGVTALRM, SIGXCPU, SIGXFSZ, + 0 + }; + struct sigaction def; + def.sa_handler = SIG_DFL; + for(i = signals; *i; i++) { + sigaction(*i, &def, NULL); + } +} + /** Execute a command with arguments in a chroot. * @param handle the context handle * @param cmd command to execute @@ -633,6 +652,7 @@ int _alpm_run_chroot(alpm_handle_t *handle, const char *cmd, char *const argv[], exit(1); } umask(0022); + _alpm_reset_signals(); execv(cmd, argv); /* execv only returns if there was an error */ fprintf(stderr, _("call to execv failed (%s)\n"), strerror(errno)); diff --git a/test/pacman/tests/TESTS b/test/pacman/tests/TESTS index b11cb511..5deb93c4 100644 --- a/test/pacman/tests/TESTS +++ b/test/pacman/tests/TESTS @@ -150,6 +150,7 @@ TESTS += test/pacman/tests/replace102.py TESTS += test/pacman/tests/replace103.py TESTS += test/pacman/tests/replace104.py TESTS += test/pacman/tests/replace110.py +TESTS += test/pacman/tests/scriptlet-signal-reset.py TESTS += test/pacman/tests/scriptlet001.py TESTS += test/pacman/tests/scriptlet002.py TESTS += test/pacman/tests/sign001.py diff --git a/test/pacman/tests/scriptlet-signal-reset.py b/test/pacman/tests/scriptlet-signal-reset.py new file mode 100644 index 00000000..27246d12 --- /dev/null +++ b/test/pacman/tests/scriptlet-signal-reset.py @@ -0,0 +1,11 @@ +self.description = "Reset signals before running scriptlets/hooks" + +p1 = pmpkg("dummy") +# check if SIGPIPE is ignored, it should be fatal, but GPGME ignores it +p1.install['post_install'] = "kill -PIPE $$; echo fail > sigpipe_was_ignored" +self.addpkg(p1) + +self.args = "-U %s" % p1.filename() + +self.addrule("PACMAN_RETCODE=0") +self.addrule("!FILE_EXIST=sigpipe_was_ignored") -- cgit v1.2.3-24-g4f1b