* [PATCH] passt: Fix error check for signal(), improve error messages
@ 2023-04-13 17:45 Stefano Brivio
0 siblings, 0 replies; only message in thread
From: Stefano Brivio @ 2023-04-13 17:45 UTC (permalink / raw)
To: passt-dev; +Cc: Valtteri Vuorikoski, David Gibson
Valtteri reports that if SIGPIPE already has a disposition set by the
parent process, such as systemd with the default setting of
IgnoreSIGPIPE=yes, signal() will return the previous value, not zero,
and this is not an error: check for SIG_ERR instead.
While at it, split messages for failures of sigaction() and signal(),
and report the actual error.
Reported-by: Valtteri Vuorikoski <vuori@notcom.org>
Fixes: 8534be076c73 ("Catch failures when installing signal handlers")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
passt.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/passt.c b/passt.c
index 7fa1170..3b9b36b 100644
--- a/passt.c
+++ b/passt.c
@@ -204,8 +204,15 @@ int main(int argc, char **argv)
name = basename(argv0);
if (strstr(name, "pasta")) {
sa.sa_handler = pasta_child_handler;
- if (sigaction(SIGCHLD, &sa, NULL) || signal(SIGPIPE, SIG_IGN))
- die("Couldn't install signal handlers");
+ if (sigaction(SIGCHLD, &sa, NULL)) {
+ die("Couldn't install signal handlers: %s",
+ strerror(errno));
+ }
+
+ if (signal(SIGPIPE, SIG_IGN) == SIG_ERR) {
+ die("Couldn't set disposition for SIGPIPE: %s",
+ strerror(errno));
+ }
c.mode = MODE_PASTA;
log_name = "pasta";
--
@@ -204,8 +204,15 @@ int main(int argc, char **argv)
name = basename(argv0);
if (strstr(name, "pasta")) {
sa.sa_handler = pasta_child_handler;
- if (sigaction(SIGCHLD, &sa, NULL) || signal(SIGPIPE, SIG_IGN))
- die("Couldn't install signal handlers");
+ if (sigaction(SIGCHLD, &sa, NULL)) {
+ die("Couldn't install signal handlers: %s",
+ strerror(errno));
+ }
+
+ if (signal(SIGPIPE, SIG_IGN) == SIG_ERR) {
+ die("Couldn't set disposition for SIGPIPE: %s",
+ strerror(errno));
+ }
c.mode = MODE_PASTA;
log_name = "pasta";
--
2.39.2
^ permalink raw reply related [flat|nested] only message in thread
only message in thread, other threads:[~2023-04-13 17:45 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-04-13 17:45 [PATCH] passt: Fix error check for signal(), improve error messages Stefano Brivio
Code repositories for project(s) associated with this public inbox
https://passt.top/passt
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for IMAP folder(s).