Re: bash: Fails to upgrade in kFreeBSD jails

[Jonathan Nieder <jrnieder@gmail.com>]

Jonathan Nieder wrote:
> Stefan Ott wrote:

>> bash.preinst: cannot set close-on-exec flag: Inappropriate ioctl for device
[...]
> Thought you might be interested in this report, since it feels like a
> libc or kernel bug.  Hints?

Of course I should give more context than that. :)

That message comes from set_cloexec(), which is defined as follows:

	void set_cloexec(int fd)
	{
		int flags = fcntl(fd, F_GETFL);
		if (flags < 0 || fcntl(fd, F_SETFL, flags | FD_CLOEXEC))
			die_errno("cannot set close-on-exec flag");
	}

It is called on /dev/null and the two file descriptors returned from
pipe() to avoid leaking file descriptors.

Presumably this should be a warning instead of a fatal error or the
set_cloexec() calls could be dropped altogether.  But why is fcntl()
failing?

Thanks,
Jonathan

diff --git i/debian/bash.preinst-lib.c w/debian/bash.preinst-lib.c
index bb13a166..701a5874 100644
--- i/debian/bash.preinst-lib.c
+++ w/debian/bash.preinst-lib.c
@@ -58,19 +58,10 @@ int exists(const char *file)
 	die_errno("cannot get status of %s", file);
 }
 
-void set_cloexec(int fd)
-{
-	int flags = fcntl(fd, F_GETFL);
-	if (flags < 0 || fcntl(fd, F_SETFL, flags | FD_CLOEXEC))
-		die_errno("cannot set close-on-exec flag");
-}
-
 void xpipe(int pipefd[2])
 {
 	if (pipe(pipefd))
 		die_errno("cannot create pipe");
-	set_cloexec(pipefd[0]);
-	set_cloexec(pipefd[1]);
 }
 
 void wait_or_die(pid_t child, const char *name, int flags)
diff --git i/debian/bash.preinst.c w/debian/bash.preinst.c
index 14baeab0..2badd2ae 100644
--- i/debian/bash.preinst.c
+++ w/debian/bash.preinst.c
@@ -85,8 +85,6 @@ static int binsh_in_filelist(const char *package)
 	 * fails, no problem; leave stderr alone in that case.
 	 */
 	sink = open("/dev/null", O_WRONLY);
-	if (sink >= 0)
-		set_cloexec(sink);
 	in = spawn_pipe(&child, cmd, sink);
 
 	/* ... | grep "^/bin/sh\$" */
diff --git i/debian/bash.preinst.h w/debian/bash.preinst.h
index 82faf497..4d4a5abb 100644
--- i/debian/bash.preinst.h
+++ w/debian/bash.preinst.h
@@ -26,7 +26,6 @@ extern NORETURN PRINTFLIKE void die_errno(const char *fmt, ...);
 extern NORETURN PRINTFLIKE void die(const char *fmt, ...);
 
 extern int exists(const char *path);
-extern void set_cloexec(int fd);
 extern void xpipe(int pipefd[2]);
 
 extern void wait_or_die(pid_t child, const char *desc, int flags);
diff --git i/debian/changelog w/debian/changelog
index 310ec061..40dcb4c5 100644
--- i/debian/changelog
+++ w/debian/changelog
@@ -1,3 +1,11 @@
+bash (4.2-2.1) local; urgency=low
+
+  * bash.preinst: Let a few file descriptors leak instead of setting
+    the close-on-exec flag. This avoids some portability gotchas.
+    Closes: #679198.
+
+ -- Jonathan Nieder <jrnieder@gmail.com>  Tue, 26 Jun 2012 20:55:36 -0500
+
 bash (4.2-2) unstable; urgency=low
 
   * Fix command-not-found location. Closes: #529313.