io-stats: Fix overwriting of client profile by the bricks

Issue: When the user executes the following command to generate
the client perf profile, if the client is on the same node as
bricks, the bricks overwrite the profile info written by clients.
Also xattr "trusted.io-stats-dump" gets set on the mount point.

setxattr -n trusted.io-stats-dump -v /tmp/iostat.log /mnt/fuse

Fix: Unwind from setxattr, when xattr is 'io-stats-dump'

Change-Id: Iba0e5df2f25f4ba3b1399ac176a3f8a916ff372e
BUG: 1322825
Signed-off-by: Poornima G <pgurusid@redhat.com>
Reviewed-on: http://review.gluster.org/13872
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Ravishankar N <ravishankar@redhat.com>
Smoke: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>

1 files changed, 43 insertions, 24 deletions

diff --git a/xlators/debug/io-stats/src/io-stats.c b/xlators/debug/io-stats/src/io-stats.c
index 3a7f53da4ab..62e85bbb99b 100644
--- a/xlators/debug/io-stats/src/io-stats.c
+++ b/xlators/debug/io-stats/src/io-stats.c
@@ -2837,32 +2837,29 @@ conditional_dump (dict_t *dict, char *key, data_t *value, void *data)
         memset (filename, 0, value->len + 1);
         memcpy (filename, data_to_str (value), value->len);
 
-        if (fnmatch ("*io*stat*dump", key, 0) == 0) {
-                pid = getpid ();
+        pid = getpid ();
 
-
-                if (!strncmp (filename, "", 1)) {
-                        gf_log (this->name, GF_LOG_ERROR, "No filename given");
-                        return -1;
-                }
-                logfp = fopen (filename, "w+");
-                if (!logfp) {
-                        gf_log (this->name, GF_LOG_ERROR, "failed to open %s "
+        if (!strncmp (filename, "", 1)) {
+                gf_log (this->name, GF_LOG_ERROR, "No filename given");
+                return -1;
+        }
+        logfp = fopen (filename, "w+");
+        if (!logfp) {
+                gf_log (this->name, GF_LOG_ERROR, "failed to open %s "
                                 "for writing", filename);
-                        return -1;
-                }
-                sprintf (dump_key, "*io*stat*%d_json_dump", pid);
-                if (fnmatch (dump_key, key, 0) == 0) {
-                        (void) ios_dump_args_init (
-                                        &args, IOS_DUMP_TYPE_JSON_FILE,
-                                        logfp);
-                } else {
-                        (void) ios_dump_args_init (&args, IOS_DUMP_TYPE_FILE,
-                                                   logfp);
-                }
-                io_stats_dump (this, &args, GF_CLI_INFO_ALL, _gf_false);
-                fclose (logfp);
+                return -1;
+        }
+        sprintf (dump_key, "*io*stat*%d_json_dump", pid);
+        if (fnmatch (dump_key, key, 0) == 0) {
+                (void) ios_dump_args_init (
+                                &args, IOS_DUMP_TYPE_JSON_FILE,
+                                logfp);
+        } else {
+                (void) ios_dump_args_init (&args, IOS_DUMP_TYPE_FILE,
+                                logfp);
         }
+        io_stats_dump (this, &args, GF_CLI_INFO_ALL, _gf_false);
+        fclose (logfp);
         return 0;
 }
 
@@ -2992,11 +2989,23 @@ out:
         return NULL;
 }
 
+static gf_boolean_t
+match_special_xattr (dict_t *d, char *k, data_t *val, void *mdata)
+{
+        gf_boolean_t ret = _gf_false;
+        if (fnmatch ("*io*stat*dump", k, 0) == 0) {
+                ret = _gf_true;
+        }
+
+        return ret;
+}
+
 int
 io_stats_setxattr (call_frame_t *frame, xlator_t *this,
                    loc_t *loc, dict_t *dict,
                    int32_t flags, dict_t *xdata)
 {
+        int ret = 0;
         struct {
                 xlator_t     *this;
                 inode_t      *inode;
@@ -3007,7 +3016,13 @@ io_stats_setxattr (call_frame_t *frame, xlator_t *this,
         stub.inode = loc->inode;
         stub.path  = loc->path;
 
-        dict_foreach (dict, conditional_dump, &stub);
+        ret = dict_foreach_match (dict, match_special_xattr, NULL,
+                                  conditional_dump, &stub);
+        if (ret > 0) {
+                /* Setxattr was on key 'io-stat-dump', hence dump and unwind
+                 * from here */
+                goto out;
+        }
 
         START_FOP_LATENCY (frame);
 
@@ -3016,6 +3031,10 @@ io_stats_setxattr (call_frame_t *frame, xlator_t *this,
                     FIRST_CHILD(this)->fops->setxattr,
                     loc, dict, flags, xdata);
         return 0;
+
+out:
+        STACK_UNWIND_STRICT (setxattr, frame, 0, 0, NULL);
+        return 0;
 }