From 57e674ae7bff996a263ca4f70ebea7606e250eb0 Mon Sep 17 00:00:00 2001

From: "Richard W.M. Jones" <rjones@redhat.com>

Date: Thu, 3 Oct 2013 18:17:39 +0100

Subject: [PATCH] daemon: Fix xfs_info parser because of new format.

The old parser had several problems: firstly it called the error path

sometimes without calling reply_with_error causing a protocol hang.

More seriously it had hard-coded line numbers, and since Fedora 21 the

output of xfs_info has changed, moving lines around.

Change the parser to be more robust against added fields by using the

first name on the line as the section name, thus 'bsize=' is

interpreted differently depending on whether it appears in the "data"

section or the "naming" section.

Ensure also that we don't call the error path without calling

reply_with_error, which is a side-effect of the above change.

(cherry picked from commit 8abd0a83b3a94e4adbd0926df818686be982cdb8)

---

 daemon/xfs.c | 114 ++++++++++++++++++++++++++++++++++++-----------------------

 1 file changed, 70 insertions(+), 44 deletions(-)

diff --git a/daemon/xfs.c b/daemon/xfs.c

index e31da8f..725f7b3 100644

--- a/daemon/xfs.c

+++ b/daemon/xfs.c

@@ -28,6 +28,8 @@

 #include "actions.h"

 #include "optgroups.h"

+#include "c-ctype.h"

+

 #define MAX_ARGS 64

 GUESTFSD_EXT_CMD(str_mkfs_xfs, mkfs.xfs);

@@ -42,7 +44,7 @@ optgroup_xfs_available (void)

   return prog_exists (str_mkfs_xfs);

 }

-/* Return everything up to the first comma or space in the input

+/* Return everything up to the first comma, equals or space in the input

  * string, strdup'ing the return value.

  */

 static char *

@@ -51,7 +53,7 @@ split_strdup (char *string)

   size_t len;

   char *ret;

-  len = strcspn (string, " ,");

+  len = strcspn (string, " ,=");

   ret = strndup (string, len);

   if (!ret) {

     reply_with_perror ("malloc");

@@ -92,6 +94,7 @@ parse_uint64 (uint64_t *ret, const char *str)

  *

  * meta-data=/dev/sda1              isize=256    agcount=4, agsize=6392 blks

  *          =                       sectsz=512   attr=2

+ *[         =                       crc=0                                    ]

  * data     =                       bsize=4096   blocks=25568, imaxpct=25

  *          =                       sunit=0      swidth=0 blks

  * naming   =version 2              bsize=4096   ascii-ci=0

@@ -99,6 +102,8 @@ parse_uint64 (uint64_t *ret, const char *str)

  *          =                       sectsz=512   sunit=0 blks, lazy-count=1

  * realtime =none                   extsz=4096   blocks=0, rtextents=0

  *

+ * [...] line only appears in Fedora >= 21

+ *

  * We may need to revisit this parsing code if the output changes

  * in future.

  */

@@ -106,6 +111,7 @@ static guestfs_int_xfsinfo *

 parse_xfs_info (char **lines)

 {

   guestfs_int_xfsinfo *ret;

+  CLEANUP_FREE char *section = NULL; /* first column, eg "meta-data", "data" */

   char *p;

   size_t i;

@@ -145,6 +151,18 @@ parse_xfs_info (char **lines)

   ret->xfs_rtextents = -1;

   for (i = 0; lines[i] != NULL; ++i) {

+    if (verbose)

+      fprintf (stderr, "xfs_info: lines[%zu] = \'%s\'\n", i, lines[i]);

+

+    if (c_isalpha (lines[i][0])) {

+      free (section);

+      section = split_strdup (lines[i]);

+      if (!section) goto error;

+

+      if (verbose)

+	fprintf (stderr, "xfs_info: new section %s\n", section);

+    }

+

     if ((p = strstr (lines[i], "meta-data="))) {

       ret->xfs_mntpoint = split_strdup (p + 10);

       if (ret->xfs_mntpoint == NULL) goto error;

@@ -168,15 +186,17 @@ parse_xfs_info (char **lines)

         goto error;

     }

     if ((p = strstr (lines[i], "sectsz="))) {

-      CLEANUP_FREE char *buf = split_strdup (p + 7);

-      if (buf == NULL) goto error;

-      if (i == 1) {

-        if (parse_uint32 (&ret->xfs_sectsize, buf) == -1)

-          goto error;

-      } else if (i == 6) {

-        if (parse_uint32 (&ret->xfs_logsectsize, buf) == -1)

-          goto error;

-      } else goto error;

+      if (section) {

+	CLEANUP_FREE char *buf = split_strdup (p + 7);

+	if (buf == NULL) goto error;

+	if (STREQ (section, "meta-data")) {

+	  if (parse_uint32 (&ret->xfs_sectsize, buf) == -1)

+	    goto error;

+	} else if (STREQ (section, "log")) {

+	  if (parse_uint32 (&ret->xfs_logsectsize, buf) == -1)

+	    goto error;

+	}

+      }

     }

     if ((p = strstr (lines[i], "attr="))) {

       CLEANUP_FREE char *buf = split_strdup (p + 5);

@@ -185,32 +205,36 @@ parse_xfs_info (char **lines)

         goto error;

     }

     if ((p = strstr (lines[i], "bsize="))) {

-      CLEANUP_FREE char *buf = split_strdup (p + 6);

-      if (buf == NULL) goto error;

-      if (i == 2) {

-        if (parse_uint32 (&ret->xfs_blocksize, buf) == -1)

-          goto error;

-      } else if (i == 4) {

-        if (parse_uint32 (&ret->xfs_dirblocksize, buf) == -1)

-          goto error;

-      } else if (i == 5) {

-        if (parse_uint32 (&ret->xfs_logblocksize, buf) == -1)

-          goto error;

-      } else goto error;

+      if (section) {

+	CLEANUP_FREE char *buf = split_strdup (p + 6);

+	if (buf == NULL) goto error;

+	if (STREQ (section, "data")) {

+	  if (parse_uint32 (&ret->xfs_blocksize, buf) == -1)

+	    goto error;

+	} else if (STREQ (section, "naming")) {

+	  if (parse_uint32 (&ret->xfs_dirblocksize, buf) == -1)

+	    goto error;

+	} else if (STREQ (section, "log")) {

+	  if (parse_uint32 (&ret->xfs_logblocksize, buf) == -1)

+	    goto error;

+	}

+      }

     }

     if ((p = strstr (lines[i], "blocks="))) {

-      CLEANUP_FREE char *buf = split_strdup (p + 7);

-      if (buf == NULL) goto error;

-      if (i == 2) {

-        if (parse_uint64 (&ret->xfs_datablocks, buf) == -1)

-          goto error;

-      } else if (i == 5) {

-        if (parse_uint32 (&ret->xfs_logblocks, buf) == -1)

-          goto error;

-      } else if (i == 7) {

-        if (parse_uint64 (&ret->xfs_rtblocks, buf) == -1)

-          goto error;

-      } else goto error;

+      if (section) {

+	CLEANUP_FREE char *buf = split_strdup (p + 7);

+	if (buf == NULL) goto error;

+	if (STREQ (section, "data")) {

+	  if (parse_uint64 (&ret->xfs_datablocks, buf) == -1)

+	    goto error;

+	} else if (STREQ (section, "log")) {

+	  if (parse_uint32 (&ret->xfs_logblocks, buf) == -1)

+	    goto error;

+	} else if (STREQ (section, "realtime")) {

+	  if (parse_uint64 (&ret->xfs_rtblocks, buf) == -1)

+	    goto error;

+	}

+      }

     }

     if ((p = strstr (lines[i], "imaxpct="))) {

       CLEANUP_FREE char *buf = split_strdup (p + 8);

@@ -219,15 +243,17 @@ parse_xfs_info (char **lines)

         goto error;

     }

     if ((p = strstr (lines[i], "sunit="))) {

-      CLEANUP_FREE char *buf = split_strdup (p + 6);

-      if (buf == NULL) goto error;

-      if (i == 3) {

-        if (parse_uint32 (&ret->xfs_sunit, buf) == -1)

-          goto error;

-      } else if (i == 6) {

-        if (parse_uint32 (&ret->xfs_logsunit, buf) == -1)

-          goto error;

-      } else goto error;

+      if (section) {

+	CLEANUP_FREE char *buf = split_strdup (p + 6);

+	if (buf == NULL) goto error;

+	if (STREQ (section, "data")) {

+	  if (parse_uint32 (&ret->xfs_sunit, buf) == -1)

+	    goto error;

+	} else if (STREQ (section, "log")) {

+	  if (parse_uint32 (&ret->xfs_logsunit, buf) == -1)

+	    goto error;

+	}

+      }

     }

     if ((p = strstr (lines[i], "swidth="))) {

       CLEANUP_FREE char *buf = split_strdup (p + 7);

-- 

1.8.3.1