mount: distinguish between MS_COMMENT flags (netdev, nofail, ...)

Since util-linux 2.12h (year 2004) there is only one flag for all
dummy options like _netdev or nofail. Unfortunately it means that when
mount(8) composes the final mount options string for mtab (or for
mount.<type> helpers) the string is generated incorrectly.

Reported-by: Dave Reisner <d@falconindy.com>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libmount/src/optmap.c b/libmount/src/optmap.c
index 4f11ce598a1678a245c14e462b737d9093206d01..68217cebe509da41f397fa50e5f9270e533a86ce 100644 (file)
--- a/libmount/src/optmap.c
+++ b/libmount/src/optmap.c
@@ -137,6 +137,10 @@ static const struct libmnt_optmap userspace_opts_map[] =
    { "group",   MNT_MS_GROUP, MNT_NOMTAB },                /* Let the group of the device mount */
    { "nogroup", MNT_MS_GROUP, MNT_INVERT | MNT_NOMTAB },   /* Device group has no special privs */
 
+   /*
+    * Note that traditional init scripts assume _netdev option in /etc/mtab to
+    * umount network block devices on shutdown.
+    */
    { "_netdev", MNT_MS_NETDEV },                           /* Device requires network */
 
    { "comment=", MNT_MS_COMMENT, MNT_NOHLPS | MNT_NOMTAB },/* fstab comment only */

diff --git a/mount/mount.c b/mount/mount.c
index 0b9acb96ae2e85f6c416b17cadc79ee915facb4a..2ce48293e23fec6b48a6ca6484adb775806716f6 100644 (file)
--- a/mount/mount.c
+++ b/mount/mount.c
@@ -110,6 +110,7 @@ struct opt_map {
   int  skip;                   /* skip in mtab option string */
   int  inv;                    /* true if flag value should be inverted */
   int  mask;                   /* flag mask value */
+  int  cmask;                  /* comments mask */
 };
 
 /* Custom mount options for our own purposes.  */
@@ -122,6 +123,9 @@ struct opt_map {
 #define MS_COMMENT     0x02000000
 #define MS_LOOP                0x00010000
 
+#define MS_COMMENT_NOFAIL      (1 << 1)
+#define MS_COMMENT_NETDEV      (1 << 2)
+
 /* Options that we keep the mount system call from seeing.  */
 #define MS_NOSYS       (MS_NOAUTO|MS_USERS|MS_USER|MS_COMMENT|MS_LOOP)
 
@@ -162,7 +166,7 @@ static const struct opt_map opt_map[] = {
   { "noowner", 0, 1, MS_OWNER  },      /* Device owner has no special privs */
   { "group",   0, 0, MS_GROUP  },      /* Let the group of the device mount */
   { "nogroup", 0, 1, MS_GROUP  },      /* Device group has no special privs */
-  { "_netdev", 0, 0, MS_COMMENT},      /* Device requires network */
+  { "_netdev", 0, 0, MS_COMMENT, MS_COMMENT_NETDEV },  /* Device requires network */
   { "comment", 0, 0, MS_COMMENT},      /* fstab comment only (kudzu,_netdev)*/
 
   /* add new options here */
@@ -201,12 +205,13 @@ static const struct opt_map opt_map[] = {
   { "strictatime", 0, 0, MS_STRICTATIME }, /* Strict atime semantics */
   { "nostrictatime", 0, 1, MS_STRICTATIME }, /* kernel default atime */
 #endif
-  { "nofail",  0, 0, MS_COMMENT},      /* Do not fail if ENOENT on dev */
+  { "nofail",  0, 0, MS_COMMENT, MS_COMMENT_NOFAIL },  /* Do not fail if ENOENT on dev */
   { NULL,      0, 0, 0         }
 };
 
 static int opt_nofail;
 static int invuser_flags;
+static int comment_flags;
 
 static const char *opt_loopdev, *opt_vfstype, *opt_offset, *opt_sizelimit,
         *opt_encryption, *opt_speed, *opt_comment, *opt_uhelper, *opt_helper;
@@ -244,6 +249,7 @@ clear_string_opts(void) {
 static void
 clear_flags_opts(void) {
        invuser_flags = 0;
+       comment_flags = 0;
        opt_nofail = 0;
 }
 
@@ -504,8 +510,11 @@ parse_opt(char *opt, int *mask, int *inv_user, char **extra_opts) {
                                verbose = 0;
                        }
 #endif
-                       if (streq(opt, "nofail"))
-                               opt_nofail = 1;
+                       if (om->mask == MS_COMMENT) {
+                               comment_flags |= om->cmask;
+                               if (om->cmask == MS_COMMENT_NOFAIL)
+                                       opt_nofail = 1;
+                       }
                        return;
                }
 
@@ -612,6 +621,8 @@ fix_opts_string (int flags, const char *extra_opts,
                        continue;
                if (om->inv || !om->mask || (flags & om->mask) != om->mask)
                        continue;
+               if (om->mask == MS_COMMENT && !(comment_flags & om->cmask))
+                       continue;
                new_opts = append_opt(new_opts, om->opt, NULL);
                flags &= ~om->mask;
        }