Initialize for fuse

fusermount-dont-feed-escaped-commans-into-mount-options.patch

@@ -0,0 +1,41 @@
+From 28bdae3d113ef479c1660a581ef720cdc33bf466 Mon Sep 17 00:00:00 2001
+From: Jann Horn <jannh@google.com>
+Date: Fri, 13 Jul 2018 15:15:36 -0700
+Subject: [PATCH] fusermount: don't feed "escaped commas" into mount options
+
+The old code permits the following behavior:
+
+$ _FUSE_COMMFD=10000 priv_strace -etrace=mount -s200 fusermount -o 'foobar=\,allow_other' mount
+mount("/dev/fuse", ".", "fuse", MS_NOSUID|MS_NODEV, "foobar=\\,allow_other,fd=3,rootmode=40000,user_id=1000,group_id=1000") = -1 EINVAL (Invalid argument)
+
+However, backslashes do not have any special meaning for the kernel here.
+
+As it happens, you can't abuse this because there is no FUSE mount option
+that takes a string value that can contain backslashes; but this is very
+brittle. Don't interpret "escape characters" in places where they don't
+work.
+
+diff --git a/util/fusermount.c b/util/fusermount.c
+index 0e1d34d..143bd4a 100644
+--- a/util/fusermount.c
++++ b/util/fusermount.c
+@@ -29,6 +29,7 @@
+ #include <sys/socket.h>
+ #include <sys/utsname.h>
+ #include <sched.h>
++#include <stdbool.h>
+ 
+ #define FUSE_COMMFD_ENV		"_FUSE_COMMFD"
+ 
+@@ -754,8 +755,10 @@ static int do_mount(const char *mnt, char **typep, mode_t rootmode,
+ 		unsigned len;
+ 		const char *fsname_str = "fsname=";
+ 		const char *subtype_str = "subtype=";
++		bool escape_ok = begins_with(s, fsname_str) ||
++				 begins_with(s, subtype_str);
+ 		for (len = 0; s[len]; len++) {
+-			if (s[len] == '\\' && s[len + 1])
++			if (escape_ok && s[len] == '\\' && s[len + 1])
+ 				len++;
+ 			else if (s[len] == ',')
+ 				break;