The fuse_opt_match(3) library function does not match options correctly.

libfuse supports option templates of the following form that can be used
to automatically parse arguments supplied on the command line.

"-p "       argument that takes an option e.g -p 22 or -p22
"-p %x"     argument that takes an option parsed like sscanf(3)
"cache=yes" matches -ocache=yes or -o cache=yes
"cache=%s"  matches -ocache=<string> or -o cache=<string>
"cache="    matches same as above but value is passed to option proc
"noatime"   matches -onoatime or -o atime

For example, it does not match options of the form "-p 22" or
"cache=yes" to the corresponding templates "-p " and "cache=yes".  This
patch fixes that and updates the regression tests accordingly.

ok mpi@

2 files changed, 66 insertions, 97 deletions

diff --git a/lib/libfuse/fuse_opt.c b/lib/libfuse/fuse_opt.c
index 873b3380399..0b026cc6038 100644
--- a/lib/libfuse/fuse_opt.c
+++ b/lib/libfuse/fuse_opt.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: fuse_opt.c,v 1.19 2017/11/16 12:56:58 helg Exp $ */
+/* $OpenBSD: fuse_opt.c,v 1.20 2017/12/11 12:01:55 helg Exp $ */
 /*
  * Copyright (c) 2013 Sylvestre Gallon <ccna.syl@gmail.com>
  * Copyright (c) 2013 Stefan Sperling <stsp@openbsd.org>
@@ -67,73 +67,35 @@ alloc_argv(struct fuse_args *args)
 	return (0);
 }
 
-static int
+/*
+ * Returns the number of characters that matched for bounds checking later.
+ */
+static size_t
 match_opt(const char *templ, const char *opt)
 {
-	const char *o, *t;
-	char *arg;
-
-	arg = strpbrk(templ, " =");
-
-	/* verify template */
-	t = templ;
-	if (*t == '-') {
-		t++;
-		if (*t == '-')
-			t++;
-		if (*t == 'o' || *t == '\0')
-			return (0);
-	}
+	size_t sep, len;
 
-	/* skip leading -, -o, and -- in option name */
-	o = opt;
-	if (*o == '-') {
-		o++;
-		if (*o == 'o' || *o == '-')
-			o++;
-	}
+	len = strlen(templ);
+	sep = strcspn(templ, "=");
 
-	/* empty option name is invalid */
-	if (*o == '\0')
-		return (0);
+	if (sep == len)
+		sep = strcspn(templ, " ");
 
-	/* match option name */
-	while (*t && *o) {
-		if (*t++ != *o++)
+	/* key=, key=%, "-k ", -k % */
+	if (sep < len && (templ[sep + 1] == '\0' || templ[sep + 1] == '%')) {
+		if (strncmp(opt, templ, sep) == 0)
+			return (sep);
+		else
 			return (0);
-		if (arg && t == arg) {
-			if (*o != ' ' && *o != '=')
-				return (0);
-			o++; /* o now points at argument */
-			if (*o == '\0')
-				return (0);
-			break;
-		}
 	}
 
-	/* match argument */
-	if (arg) {
-		if (t != arg)
-			return (0);
-		t++;
-		/* does template have an argument? */
-		if (*t != '%' && *t != '\0')
-			return (0);
-		if (*t == '%' && t[1] == '\0')
-			return (0);
-		/* yes it does, consume argument in opt */
-		while (*o && *o != ' ')
-			o++;
-	} else if (*t != '\0')
-		return (0);
+	if (strcmp(opt, templ) == 0)
+		return (len);
 
-	/* we should have consumed entire opt string */
-	if (*o != '\0')
-		return (0);
-
-	return (1);
+	return (0);
 }
 
+
 static int
 add_opt(char **opts, const char *opt)
 {
diff --git a/regress/lib/libfuse/fuse-opt-match.c b/regress/lib/libfuse/fuse-opt-match.c
index 71daa0245f3..830f456ed3a 100644
--- a/regress/lib/libfuse/fuse-opt-match.c
+++ b/regress/lib/libfuse/fuse-opt-match.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) Sylvestre Gallon <ccna.syl@gmail.com>
+ * Copyright (c) 2017 Helg Bredow <xx404@msn.com>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -14,55 +14,62 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-#include <string.h>
+#include <assert.h>
+#include <stddef.h>
 #include <fuse_opt.h>
 
-const struct fuse_opt nullopts[] = {
+static const struct fuse_opt emptyopts[] = {
 	FUSE_OPT_END
 };
 
-const int nullresults[] = {
-	0, 0, 0, 0, 0, 0
-};
-
-const struct fuse_opt badopts[] = {
-	FUSE_OPT_KEY("-p ", 0),
-	FUSE_OPT_KEY("-C", 1),
-	FUSE_OPT_KEY("-V", 3),
-	FUSE_OPT_KEY("--version", 3),
-	FUSE_OPT_KEY("-h", 2),
+static const struct fuse_opt opts[] = {
+	FUSE_OPT_KEY("-p ",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("-C",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("-V",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("--version",	FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("-h",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("const=false",	FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("cache=no",	FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("cache=yes",	FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("debug",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("ro",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("--foo=",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("bars=%s",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("--fool=%lu",	FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("-x ",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("-n %u",		FUSE_OPT_KEY_DISCARD),
+	FUSE_OPT_KEY("-P",		FUSE_OPT_KEY_DISCARD),
 	FUSE_OPT_END
 };
 
-static int
-match_opts(const struct fuse_opt *opts, const int *results)
+int
+main(void)
 {
-	if (fuse_opt_match(opts, NULL) != 0)
-		return (1);
+	assert(fuse_opt_match(emptyopts, "debug")	==	0);
 
-	if (fuse_opt_match(opts, "bar=") != results[0])
-		return (3);
-	if (fuse_opt_match(opts, "--foo=") != results[1])
-		return (4);
-	if (fuse_opt_match(opts, "bar=%s") != results[2])
-		return (5);
-	if (fuse_opt_match(opts, "--foo=%lu") != results[3])
-		return (6);
-	if (fuse_opt_match(opts, "-x ") != results[4])
-		return (7);
-	if (fuse_opt_match(opts, "-x %s") != results[5])
-		return (8);
+	assert(fuse_opt_match(opts, NULL)		==	0);
+	assert(fuse_opt_match(opts, "-p ")		==	1);
+	assert(fuse_opt_match(opts, "-C")		==	1);
+	assert(fuse_opt_match(opts, "-c")		==	0);
+	assert(fuse_opt_match(opts, "-V")		==	1);
+	assert(fuse_opt_match(opts, "--version")	==	1);
+	assert(fuse_opt_match(opts, "-h")		==	1);
+	assert(fuse_opt_match(opts, "const=false")	==	1);
+	assert(fuse_opt_match(opts, "const=falsefalse")	==	0);
+	assert(fuse_opt_match(opts, "cache=no")		==	1);
+	assert(fuse_opt_match(opts, "cache=yes")	==	1);
+	assert(fuse_opt_match(opts, "debug")		==	1);
+	assert(fuse_opt_match(opts, "ro")		==	1);
+	assert(fuse_opt_match(opts, "ro_fallback")	==	0);
+	assert(fuse_opt_match(opts, "--foo=bar")	==	1);
+	assert(fuse_opt_match(opts, "bars=foo")		==	1);
+	assert(fuse_opt_match(opts, "--fool=bool")	==	1);
+	assert(fuse_opt_match(opts, "--fool=1")		==	1);
+	assert(fuse_opt_match(opts, "-x bar")		==	1);
+	assert(fuse_opt_match(opts, "-xbar")		==	1);
+	assert(fuse_opt_match(opts, "-n 100")		==	1);
+	assert(fuse_opt_match(opts, "-n100")		==	1);
+	assert(fuse_opt_match(opts, "-P")		==	1);
 
 	return (0);
 }
-
-int
-main(int ac, char **av)
-{
-	if (match_opts(nullopts, nullresults) != 0)
-		return (1);
-	if (match_opts(badopts, nullresults) != 0)
-		return (1);
-	return (0);
-}
-