Support negated fstab options

We would ignore options like "fail" and "auto", and for any option
which takes a value the first assignment would win. Repeated and
options equivalent to the default are rarely used, but they have been
documented forever, and people might use them. Especially on the
kernel command line it is easier to append a repeated or negated
option at the end.

5 files changed, 35 insertions, 15 deletions

diff --git a/src/cryptsetup/cryptsetup-generator.c b/src/cryptsetup/cryptsetup-generator.c
index 3657890df4..27b2360d24 100644
--- a/src/cryptsetup/cryptsetup-generator.c
+++ b/src/cryptsetup/cryptsetup-generator.c
@@ -67,8 +67,8 @@ static int create_disk(
         assert(name);
         assert(device);
 
-        noauto = fstab_test_option(options, "noauto\0");
-        nofail = fstab_test_option(options, "nofail\0");
+        noauto = fstab_test_yes_no_option(options, "noauto\0" "auto\0");
+        nofail = fstab_test_yes_no_option(options, "nofail\0" "fail\0");
         tmp = fstab_test_option(options, "tmp\0");
         swap = fstab_test_option(options, "swap\0");
 
diff --git a/src/cryptsetup/cryptsetup.c b/src/cryptsetup/cryptsetup.c
index 15dea7b65b..e6b37acb86 100644
--- a/src/cryptsetup/cryptsetup.c
+++ b/src/cryptsetup/cryptsetup.c
@@ -69,7 +69,7 @@ static int parse_one_option(const char *option) {
         assert(option);
 
         /* Handled outside of this tool */
-        if (streq(option, "noauto") || streq(option, "nofail"))
+        if (STR_IN_SET(option, "noauto", "auto", "nofail", "fail"))
                 return 0;
 
         if (startswith(option, "cipher=")) {
diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index 64eed49523..bc4c1556ca 100644
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -135,17 +135,15 @@ static int add_swap(
 static bool mount_is_network(struct mntent *me) {
         assert(me);
 
-        return
-                hasmntopt(me, "_netdev") ||
-                fstype_is_network(me->mnt_type);
+        return fstab_test_option(me->mnt_opts, "_netdev\0") ||
+               fstype_is_network(me->mnt_type);
 }
 
 static bool mount_in_initrd(struct mntent *me) {
         assert(me);
 
-        return
-                hasmntopt(me, "x-initrd.mount") ||
-                streq(me->mnt_dir, "/usr");
+        return fstab_test_option(me->mnt_opts, "x-initrd.mount\0") ||
+               streq(me->mnt_dir, "/usr");
 }
 
 static int add_mount(
@@ -344,8 +342,8 @@ static int parse_fstab(bool initrd) {
                 if (is_path(where))
                         path_kill_slashes(where);
 
-                noauto = !!hasmntopt(me, "noauto");
-                nofail = !!hasmntopt(me, "nofail");
+                noauto = fstab_test_yes_no_option(me->mnt_opts, "noauto\0" "auto\0");
+                nofail = fstab_test_yes_no_option(me->mnt_opts, "nofail\0" "fail\0");
                 log_debug("Found entry what=%s where=%s type=%s nofail=%s noauto=%s",
                           what, where, me->mnt_type,
                           yes_no(noauto), yes_no(nofail));
@@ -356,10 +354,9 @@ static int parse_fstab(bool initrd) {
                         bool automount;
                         const char *post;
 
-                        automount =
-                                  hasmntopt(me, "comment=systemd.automount") ||
-                                  hasmntopt(me, "x-systemd.automount");
-
+                        automount = fstab_test_option(me->mnt_opts,
+                                                      "comment=systemd.automount\0"
+                                                      "x-systemd.automount\0");
                         if (initrd)
                                 post = SPECIAL_INITRD_FS_TARGET;
                         else if (mount_in_initrd(me))
diff --git a/src/shared/fstab-util.h b/src/shared/fstab-util.h
index 39ddb71ef4..9f6b32eaf4 100644
--- a/src/shared/fstab-util.h
+++ b/src/shared/fstab-util.h
@@ -23,6 +23,7 @@
 
 #include <stdbool.h>
 #include <stddef.h>
+#include "macro.h"
 
 int fstab_filter_options(const char *opts, const char *names,
                          const char **namefound, char **value, char **filtered);
@@ -32,3 +33,16 @@ static inline bool fstab_test_option(const char *opts, const char *names) {
 }
 
 int fstab_find_pri(const char *options, int *ret);
+
+static inline bool fstab_test_yes_no_option(const char *opts, const char *yes_no) {
+        int r;
+        const char *opt;
+
+        /* If first name given is last, return 1.
+         * If second name given is last or neither is found, return 0. */
+
+        r = fstab_filter_options(opts, yes_no, &opt, NULL, NULL);
+        assert(r >= 0);
+
+        return opt == yes_no;
+}
diff --git a/src/test/test-fstab-util.c b/src/test/test-fstab-util.c
index ddf965dde5..284484d656 100644
--- a/src/test/test-fstab-util.c
+++ b/src/test/test-fstab-util.c
@@ -107,6 +107,15 @@ static void test_fstab_filter_options(void) {
         do_fstab_filter_options("", "opt\0", 0, NULL, NULL, "");
 }
 
+static void test_fstab_yes_no_option(void) {
+        assert_se(fstab_test_yes_no_option("nofail,fail,nofail", "nofail\0fail\0") == true);
+        assert_se(fstab_test_yes_no_option("nofail,nofail,fail", "nofail\0fail\0") == false);
+        assert_se(fstab_test_yes_no_option("abc,cde,afail", "nofail\0fail\0") == false);
+        assert_se(fstab_test_yes_no_option("nofail,fail=0,nofail=0", "nofail\0fail\0") == true);
+        assert_se(fstab_test_yes_no_option("nofail,nofail=0,fail=0", "nofail\0fail\0") == false);
+}
+
 int main(void) {
         test_fstab_filter_options();
+        test_fstab_yes_no_option();
 }