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[PATCH 4/5] common-main: call restore_sigpipe_to_default()

From
Jeff King <peff@peff.net>
Date
Jul 1, 2016, 06:06 UTC
Message-ID
<20160701060635.GD4593@sigill.intra.peff.net>
In-Reply-To
<20160701055532.GA4488@sigill.intra.peff.net>

This is another safety/sanity setup that should be in force everywhere, but which we only applied in git.c. This did catch most cases, since even external commands are typically run via "git ..." (and the restoration applies to sub-processes, too). But there were cases we missed, such as somebody calling git-upload-pack directly via ssh, or scripts which use dashed external commands directly.

Signed-off-by: Jeff King <peff@peff.net>
---
 common-main.c | 23 +++++++++++++++++++++++
 git.c         | 23 -----------------------
 2 files changed, 23 insertions(+), 23 deletions(-)
diff --git a/common-main.c b/common-main.c
index 353c6ea..20e55ef 100644
--- a/common-main.c
+++ b/common-main.c
@@ -1,6 +1,27 @@
 #include "cache.h"
 #include "exec_cmd.h"
 
+/*
+ * Many parts of Git have subprograms communicate via pipe, expect the
+ * upstream of a pipe to die with SIGPIPE when the downstream of a
+ * pipe does not need to read all that is written.  Some third-party
+ * programs that ignore or block SIGPIPE for their own reason forget
+ * to restore SIGPIPE handling to the default before spawning Git and
+ * break this carefully orchestrated machinery.
+ *
+ * Restore the way SIGPIPE is handled to default, which is what we
+ * expect.
+ */
+static void restore_sigpipe_to_default(void)
+{
+	sigset_t unblock;
+
+	sigemptyset(&unblock);
+	sigaddset(&unblock, SIGPIPE);
+	sigprocmask(SIG_UNBLOCK, &unblock, NULL);
+	signal(SIGPIPE, SIG_DFL);
+}
+
 int main(int argc, char **av)
 {
 	/*
@@ -18,5 +39,7 @@ int main(int argc, char **av)
 
 	argv[0] = git_extract_argv0_path(argv[0]);
 
+	restore_sigpipe_to_default();
+
 	return cmd_main(argc, argv);
 }
diff --git a/git.c b/git.c
index b65083c..ccb24fd 100644
--- a/git.c
+++ b/git.c
@@ -609,27 +609,6 @@ static int run_argv(int *argcp, const char ***argv)
 	return done_alias;
 }
 
-/*
- * Many parts of Git have subprograms communicate via pipe, expect the
- * upstream of a pipe to die with SIGPIPE when the downstream of a
- * pipe does not need to read all that is written.  Some third-party
- * programs that ignore or block SIGPIPE for their own reason forget
- * to restore SIGPIPE handling to the default before spawning Git and
- * break this carefully orchestrated machinery.
- *
- * Restore the way SIGPIPE is handled to default, which is what we
- * expect.
- */
-static void restore_sigpipe_to_default(void)
-{
-	sigset_t unblock;
-
-	sigemptyset(&unblock);
-	sigaddset(&unblock, SIGPIPE);
-	sigprocmask(SIG_UNBLOCK, &unblock, NULL);
-	signal(SIGPIPE, SIG_DFL);
-}
-
 int cmd_main(int argc, const char **argv)
 {
 	const char *cmd;
@@ -639,8 +618,6 @@ int cmd_main(int argc, const char **argv)
 	if (!cmd)
 		cmd = "git-help";
 
-	restore_sigpipe_to_default();
-
 	git_setup_gettext();
 
 	trace_command_performance(argv);
-- 
2.9.0.317.g65b4e7c
Previous: Jeff KingNext: Johannes Schindelin
Message 14 of 21 in “git-credentials-store.exe crash”
  1. dmh@ucar.eduJun 30, 2016
  2. Jeff KingJul 1, 2016
  3. 0/5 consistent setup code for external commandsJeff King, Jul 1, 2016
  4. 1/5 add an extra level of indirection to main()Jeff King, Jul 1, 2016
  5. Johannes SchindelinJul 1, 2016
  6. Jeff KingJul 1, 2016
  7. Johannes SchindelinJul 1, 2016
  8. Jeff KingJul 1, 2016
  9. Johannes SchindelinJul 2, 2016
  10. 2/5 common-main: call git_extract_argv0_path()Jeff King, Jul 1, 2016
  11. Johannes SchindelinJul 1, 2016
  12. 3/5 common-main: call sanitize_stdfds()Jeff King, Jul 1, 2016
  13. 5/5 common-main: call git_setup_gettext()Jeff King, Jul 1, 2016
  14. 4/5 common-main: call restore_sigpipe_to_default()Jeff King, Jul 1, 2016
  15. Johannes SchindelinJul 1, 2016
  16. Junio C HamanoJul 1, 2016
  17. Jeff KingJul 1, 2016
  18. Junio C HamanoJul 6, 2016
  19. Johannes SchindelinJul 6, 2016
  20. Johannes SchindelinJul 1, 2016
  21. Jeff KingJul 1, 2016

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