From 2bf509d96d84c3336d08375e8af34d1b85ee71c8 Mon Sep 17 00:00:00 2001
From: Menglong Dong <dong.menglong@zte.com.cn>
Date: Sat, 5 Dec 2020 22:14:42 -0800
Subject: [PATCH] coredump: fix core_pattern parse error
Git-commit: 2bf509d96d84c3336d08375e8af34d1b85ee71c8
Patch-mainline: v5.10-rc7
References: git-fixes

'format_corename()' will splite 'core_pattern' on spaces when it is in
pipe mode, and take helper_argv[0] as the path to usermode executable.
It works fine in most cases.

However, if there is a space between '|' and '/file/path', such as
'| /usr/lib/systemd/systemd-coredump %P %u %g', then helper_argv[0] will
be parsed as '', and users will get a 'Core dump to | disabled'.

It is not friendly to users, as the pattern above was valid previously.
Fix this by ignoring the spaces between '|' and '/file/path'.

Fixes: 315c69261dd3 ("coredump: split pipe command whitespace before expanding template")
Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Wise <pabs3@bonedaddy.net>
Cc: Jakub Wilk <jwilk@jwilk.net> [https://bugs.debian.org/924398]
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/5fb62870.1c69fb81.8ef5d.af76@mx.google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 fs/coredump.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/coredump.c b/fs/coredump.c
index 0cd9056d79cc..c6acfc694f65 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -229,7 +229,8 @@ static int format_corename(struct core_name *cn, struct coredump_params *cprm,
 		 */
 		if (ispipe) {
 			if (isspace(*pat_ptr)) {
-				was_space = true;
+				if (cn->used != 0)
+					was_space = true;
 				pat_ptr++;
 				continue;
 			} else if (was_space) {
-- 
2.26.2