From db803036ada7d61d096783726f9771b3fc540370 Mon Sep 17 00:00:00 2001
From: Vincent Minet <v.minet@criteo.com>
Date: Fri, 8 May 2020 00:14:22 +0200
Subject: [PATCH] umh: fix memory leak on execve failure
Git-commit: db803036ada7d61d096783726f9771b3fc540370
Patch-mainline: v5.7-rc6
References: git-fixes
If a UMH process created by fork_usermode_blob() fails to execute,
a pair of struct file allocated by umh_pipe_setup() will leak.
Under normal conditions, the caller (like bpfilter) needs to manage the
lifetime of the UMH and its two pipes. But when fork_usermode_blob()
fails, the caller doesn't really have a way to know what needs to be
done. It seems better to do the cleanup ourselves in this case.
Fixes: 449325b52b7a ("umh: introduce fork_usermode_blob() helper")
Signed-off-by: Vincent Minet <v.minet@criteo.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
kernel/umh.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/kernel/umh.c b/kernel/umh.c
index 7f255b5a8845..20d51e0957e0 100644
--- a/kernel/umh.c
+++ b/kernel/umh.c
@@ -475,6 +475,12 @@ static void umh_clean_and_save_pid(struct subprocess_info *info)
{
struct umh_info *umh_info = info->data;
+ /* cleanup if umh_pipe_setup() was successful but exec failed */
+ if (info->pid && info->retval) {
+ fput(umh_info->pipe_to_umh);
+ fput(umh_info->pipe_from_umh);
+ }
+
argv_free(info->argv);
umh_info->pid = info->pid;
}
--
2.16.4