[libvirt] [PATCH] util: Alter return value of virReadFCHost and fix mem leak
John Ferlan
jferlan at redhat.com
Tue Oct 11 21:25:49 UTC 2016
https://bugzilla.redhat.com/show_bug.cgi?id=1357416
Rather than return a 0 or -1 and the *result string, return just the result
string to the caller. Alter all the callers to handle the different return.
As a side effect or result of this, it's much clearer that we cannot just
assign the returned string into the scsi_host wwnn, wwpn, and fabric_wwn
fields - rather we should fetch a temporary string, then as long as our
fetch was good, VIR_FREE what may have been there, and STEAL what we just got.
This fixes a memory leak in the virNodeDeviceCreateXML code path through
find_new_device and nodeDeviceLookupSCSIHostByWWN which will continually
call nodeDeviceSysfsGetSCSIHostCaps until the expected wwnn/wwpn is found
in the device object capabilities.
Signed-off-by: John Ferlan <jferlan at redhat.com>
---
I suppose I could have made two patches out of this, but it felt like
overkill once I realized what the issue was. OK a third one line patch
could have been added to change the virGetFCHostNameByWWN comment as well,
but that'd really be overkill.
src/node_device/node_device_linux_sysfs.c | 55 ++++++++++++-------------------
src/util/virutil.c | 34 ++++++++-----------
src/util/virutil.h | 9 +++--
tests/fchosttest.c | 30 ++++++-----------
4 files changed, 49 insertions(+), 79 deletions(-)
diff --git a/src/node_device/node_device_linux_sysfs.c b/src/node_device/node_device_linux_sysfs.c
index 549d32c..be99c41 100644
--- a/src/node_device/node_device_linux_sysfs.c
+++ b/src/node_device/node_device_linux_sysfs.c
@@ -44,8 +44,7 @@ VIR_LOG_INIT("node_device.node_device_linux_sysfs");
int
nodeDeviceSysfsGetSCSIHostCaps(virNodeDevCapDataPtr d)
{
- char *max_vports = NULL;
- char *vports = NULL;
+ char *tmp = NULL;
int ret = -1;
if (virReadSCSIUniqueId(NULL, d->scsi_host.host,
@@ -59,64 +58,53 @@ nodeDeviceSysfsGetSCSIHostCaps(virNodeDevCapDataPtr d)
if (virIsCapableFCHost(NULL, d->scsi_host.host)) {
d->scsi_host.flags |= VIR_NODE_DEV_CAP_FLAG_HBA_FC_HOST;
- if (virReadFCHost(NULL,
- d->scsi_host.host,
- "port_name",
- &d->scsi_host.wwpn) < 0) {
+ if (!(tmp = virReadFCHost(NULL, d->scsi_host.host, "port_name"))) {
VIR_WARN("Failed to read WWPN for host%d", d->scsi_host.host);
goto cleanup;
}
+ VIR_FREE(d->scsi_host.wwpn);
+ VIR_STEAL_PTR(d->scsi_host.wwpn, tmp);
- if (virReadFCHost(NULL,
- d->scsi_host.host,
- "node_name",
- &d->scsi_host.wwnn) < 0) {
+ if (!(tmp = virReadFCHost(NULL, d->scsi_host.host, "node_name"))) {
VIR_WARN("Failed to read WWNN for host%d", d->scsi_host.host);
goto cleanup;
}
+ VIR_FREE(d->scsi_host.wwnn);
+ VIR_STEAL_PTR(d->scsi_host.wwnn, tmp);
- if (virReadFCHost(NULL,
- d->scsi_host.host,
- "fabric_name",
- &d->scsi_host.fabric_wwn) < 0) {
+ if (!(tmp = virReadFCHost(NULL, d->scsi_host.host, "fabric_name"))) {
VIR_WARN("Failed to read fabric WWN for host%d",
d->scsi_host.host);
goto cleanup;
}
+ VIR_FREE(d->scsi_host.fabric_wwn);
+ VIR_STEAL_PTR(d->scsi_host.fabric_wwn, tmp);
}
if (virIsCapableVport(NULL, d->scsi_host.host)) {
d->scsi_host.flags |= VIR_NODE_DEV_CAP_FLAG_HBA_VPORT_OPS;
- if (virReadFCHost(NULL,
- d->scsi_host.host,
- "max_npiv_vports",
- &max_vports) < 0) {
+ if (!(tmp = virReadFCHost(NULL, d->scsi_host.host,
+ "max_npiv_vports"))) {
VIR_WARN("Failed to read max_npiv_vports for host%d",
d->scsi_host.host);
goto cleanup;
}
- if (virReadFCHost(NULL,
- d->scsi_host.host,
- "npiv_vports_inuse",
- &vports) < 0) {
- VIR_WARN("Failed to read npiv_vports_inuse for host%d",
- d->scsi_host.host);
+ if (virStrToLong_i(tmp, NULL, 10, &d->scsi_host.max_vports) < 0) {
+ VIR_WARN("Failed to parse value of max_npiv_vports '%s'", tmp);
goto cleanup;
}
- if (virStrToLong_i(max_vports, NULL, 10,
- &d->scsi_host.max_vports) < 0) {
- VIR_WARN("Failed to parse value of max_npiv_vports '%s'",
- max_vports);
+ if (!(tmp = virReadFCHost(NULL, d->scsi_host.host,
+ "npiv_vports_inuse"))) {
+ VIR_WARN("Failed to read npiv_vports_inuse for host%d",
+ d->scsi_host.host);
goto cleanup;
}
- if (virStrToLong_i(vports, NULL, 10,
- &d->scsi_host.vports) < 0) {
- VIR_WARN("Failed to parse value of npiv_vports_inuse '%s'",
- vports);
+ if (virStrToLong_i(tmp, NULL, 10, &d->scsi_host.vports) < 0) {
+ VIR_WARN("Failed to parse value of npiv_vports_inuse '%s'", tmp);
goto cleanup;
}
}
@@ -132,8 +120,7 @@ nodeDeviceSysfsGetSCSIHostCaps(virNodeDevCapDataPtr d)
VIR_FREE(d->scsi_host.wwpn);
VIR_FREE(d->scsi_host.fabric_wwn);
}
- VIR_FREE(max_vports);
- VIR_FREE(vports);
+ VIR_FREE(tmp);
return ret;
}
diff --git a/src/util/virutil.c b/src/util/virutil.c
index b57a195..2459d2d 100644
--- a/src/util/virutil.c
+++ b/src/util/virutil.c
@@ -2008,24 +2008,21 @@ virGetSCSIHostNameByParentaddr(unsigned int domain,
* @sysfs_prefix: "fc_host" sysfs path, defaults to SYSFS_FC_HOST_PATH
* @host: Host number, E.g. 5 of "fc_host/host5"
* @entry: Name of the sysfs entry to read
- * @result: Return the entry value as string
*
* Read the value of sysfs "fc_host" entry.
*
- * Returns 0 on success, and @result is filled with the entry value.
- * as string, Otherwise returns -1. Caller must free @result after
- * use.
+ * Returns result as a stringon success, caller must free @result after
+ * Otherwise returns NULL.
*/
-int
+char *
virReadFCHost(const char *sysfs_prefix,
int host,
- const char *entry,
- char **result)
+ const char *entry)
{
char *sysfs_path = NULL;
char *p = NULL;
- int ret = -1;
char *buf = NULL;
+ char *result = NULL;
if (virAsprintf(&sysfs_path, "%s/host%d/%s",
sysfs_prefix ? sysfs_prefix : SYSFS_FC_HOST_PATH,
@@ -2043,14 +2040,12 @@ virReadFCHost(const char *sysfs_prefix,
else
p = buf;
- if (VIR_STRDUP(*result, p) < 0)
- goto cleanup;
+ ignore_value(VIR_STRDUP(result, p));
- ret = 0;
cleanup:
VIR_FREE(sysfs_path);
VIR_FREE(buf);
- return ret;
+ return result;
}
bool
@@ -2171,7 +2166,7 @@ virManageVport(const int parent_host,
return ret;
}
-/* virGetHostNameByWWN:
+/* virGetFCHostNameByWWN:
*
* Iterate over the sysfs tree to get FC host name (e.g. host5)
* by the provided "wwnn,wwpn" pair.
@@ -2298,7 +2293,7 @@ virFindFCHostCapableVport(const char *sysfs_prefix)
if (!virIsCapableVport(prefix, host))
continue;
- if (virReadFCHost(prefix, host, "port_state", &state) < 0) {
+ if (!(state = virReadFCHost(prefix, host, "port_state"))) {
VIR_DEBUG("Failed to read port_state for host%d", host);
continue;
}
@@ -2310,12 +2305,12 @@ virFindFCHostCapableVport(const char *sysfs_prefix)
}
VIR_FREE(state);
- if (virReadFCHost(prefix, host, "max_npiv_vports", &max_vports) < 0) {
+ if (!(max_vports = virReadFCHost(prefix, host, "max_npiv_vports"))) {
VIR_DEBUG("Failed to read max_npiv_vports for host%d", host);
continue;
}
- if (virReadFCHost(prefix, host, "npiv_vports_inuse", &vports) < 0) {
+ if (!(vports = virReadFCHost(prefix, host, "npiv_vports_inuse"))) {
VIR_DEBUG("Failed to read npiv_vports_inuse for host%d", host);
VIR_FREE(max_vports);
continue;
@@ -2379,14 +2374,13 @@ virGetSCSIHostNameByParentaddr(unsigned int domain ATTRIBUTE_UNUSED,
return NULL;
}
-int
+char *
virReadFCHost(const char *sysfs_prefix ATTRIBUTE_UNUSED,
int host ATTRIBUTE_UNUSED,
- const char *entry ATTRIBUTE_UNUSED,
- char **result ATTRIBUTE_UNUSED)
+ const char *entry ATTRIBUTE_UNUSED)
{
virReportSystemError(ENOSYS, "%s", _("Not supported on this platform"));
- return -1;
+ return NULL;
}
bool
diff --git a/src/util/virutil.h b/src/util/virutil.h
index 703ec53..8c0d83c 100644
--- a/src/util/virutil.h
+++ b/src/util/virutil.h
@@ -182,11 +182,10 @@ virGetSCSIHostNameByParentaddr(unsigned int domain,
unsigned int slot,
unsigned int function,
unsigned int unique_id);
-int virReadFCHost(const char *sysfs_prefix,
- int host,
- const char *entry,
- char **result)
- ATTRIBUTE_NONNULL(3) ATTRIBUTE_NONNULL(4);
+char *virReadFCHost(const char *sysfs_prefix,
+ int host,
+ const char *entry)
+ ATTRIBUTE_NONNULL(3);
bool virIsCapableFCHost(const char *sysfs_prefix, int host);
bool virIsCapableVport(const char *sysfs_prefix, int host);
diff --git a/tests/fchosttest.c b/tests/fchosttest.c
index e9b89a7..a08a2e8 100644
--- a/tests/fchosttest.c
+++ b/tests/fchosttest.c
@@ -68,35 +68,25 @@ test3(const void *data ATTRIBUTE_UNUSED)
char *vports = NULL;
int ret = -1;
- if (virReadFCHost(TEST_FC_HOST_PREFIX,
- TEST_FC_HOST_NUM,
- "node_name",
- &wwnn) < 0)
+ if (!(wwnn = virReadFCHost(TEST_FC_HOST_PREFIX, TEST_FC_HOST_NUM,
+ "node_name")))
return -1;
- if (virReadFCHost(TEST_FC_HOST_PREFIX,
- TEST_FC_HOST_NUM,
- "port_name",
- &wwpn) < 0)
+ if (!(wwpn = virReadFCHost(TEST_FC_HOST_PREFIX, TEST_FC_HOST_NUM,
+ "port_name")))
goto cleanup;
- if (virReadFCHost(TEST_FC_HOST_PREFIX,
- TEST_FC_HOST_NUM,
- "fabric_name",
- &fabric_wwn) < 0)
+ if (!(fabric_wwn = virReadFCHost(TEST_FC_HOST_PREFIX, TEST_FC_HOST_NUM,
+ "fabric_name")))
goto cleanup;
- if (virReadFCHost(TEST_FC_HOST_PREFIX,
- TEST_FC_HOST_NUM,
- "max_npiv_vports",
- &max_vports) < 0)
+ if (!(max_vports = virReadFCHost(TEST_FC_HOST_PREFIX, TEST_FC_HOST_NUM,
+ "max_npiv_vports")))
goto cleanup;
- if (virReadFCHost(TEST_FC_HOST_PREFIX,
- TEST_FC_HOST_NUM,
- "npiv_vports_inuse",
- &vports) < 0)
+ if (!(vports = virReadFCHost(TEST_FC_HOST_PREFIX, TEST_FC_HOST_NUM,
+ "npiv_vports_inuse")))
goto cleanup;
if (STRNEQ(expect_wwnn, wwnn) ||
--
2.7.4
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