Re: [PATCH] network: refactor networkSetIPv6Sysctls() for proper g_autofree usage

[Ján Tomko]

On a Friday in 2020, Laine Stump wrote:

This function used the same char* three times for different purposes,
freeing it after each use. Since we don't want to ever manually free
an autofree'd pointer, modify it to use three separate char*, and make
them all g_autofree.

Signed-off-by: Laine Stump 
---
This was suggested by Jan in

 https://www.redhat.com/archives/libvir-list/2020-July/msg00805.html



Oops, I should have been more verboser.

Just a note for the mailing list that this was resolved by my:
commit 5c50d1dda5664d480e6370111c0218947706bd31
network: split out networkSetIPv6Sysctl

which removed the repetitive use by moving it to a separate function.

Jano


pushing this patch along with the patch 5 referenced there will permit
pushing patch 06/15 of that series unmodified.

src/network/bridge_driver.c | 32 
1 file changed, 16 insertions(+), 16 deletions(-)


signature.asc
Description: PGP signature

[PATCH] network: refactor networkSetIPv6Sysctls() for proper g_autofree usage

[Laine Stump]

This function used the same char* three times for different purposes,
freeing it after each use. Since we don't want to ever manually free
an autofree'd pointer, modify it to use three separate char*, and make
them all g_autofree.

Signed-off-by: Laine Stump 
---
This was suggested by Jan in

  https://www.redhat.com/archives/libvir-list/2020-July/msg00805.html

pushing this patch along with the patch 5 referenced there will permit
pushing patch 06/15 of that series unmodified.

 src/network/bridge_driver.c | 32 
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
index dd8f34e543..6d341dba7c 100644
--- a/src/network/bridge_driver.c
+++ b/src/network/bridge_driver.c
@@ -2248,7 +2248,9 @@ static int
 networkSetIPv6Sysctls(virNetworkObjPtr obj)
 {
 virNetworkDefPtr def = virNetworkObjGetDef(obj);
-char *field = NULL;
+g_autofree char *disable_ipv6 = NULL;
+g_autofree char *accept_ra = NULL;
+g_autofree char *autoconf = NULL;
 int ret = -1;
 bool enableIPv6 = !!virNetworkDefGetIPByIndex(def, AF_INET6, 0);
 
@@ -2256,10 +2258,10 @@ networkSetIPv6Sysctls(virNetworkObjPtr obj)
  * network. But also unset it if there *are* ipv6 addresses, as we
  * can't be sure of its default value.
  */
-field = g_strdup_printf(SYSCTL_PATH "/net/ipv6/conf/%s/disable_ipv6",
-def->bridge);
+disable_ipv6 = g_strdup_printf(SYSCTL_PATH 
"/net/ipv6/conf/%s/disable_ipv6",
+   def->bridge);
 
-if (access(field, W_OK) < 0 && errno == ENOENT) {
+if (access(disable_ipv6, W_OK) < 0 && errno == ENOENT) {
 if (!enableIPv6)
 VIR_DEBUG("ipv6 appears to already be disabled on %s",
   def->bridge);
@@ -2267,13 +2269,12 @@ networkSetIPv6Sysctls(virNetworkObjPtr obj)
 goto cleanup;
 }
 
-if (virFileWriteStr(field, enableIPv6 ? "0" : "1", 0) < 0) {
+if (virFileWriteStr(disable_ipv6, enableIPv6 ? "0" : "1", 0) < 0) {
 virReportSystemError(errno,
  _("cannot write to %s to enable/disable IPv6 "
-   "on bridge %s"), field, def->bridge);
+   "on bridge %s"), disable_ipv6, def->bridge);
 goto cleanup;
 }
-VIR_FREE(field);
 
 /* The rest of the ipv6 sysctl tunables should always be set the
  * same, whether or not we're using ipv6 on this bridge.
@@ -2282,30 +2283,29 @@ networkSetIPv6Sysctls(virNetworkObjPtr obj)
 /* Prevent guests from hijacking the host network by sending out
  * their own router advertisements.
  */
-field = g_strdup_printf(SYSCTL_PATH "/net/ipv6/conf/%s/accept_ra",
-def->bridge);
+accept_ra = g_strdup_printf(SYSCTL_PATH "/net/ipv6/conf/%s/accept_ra",
+def->bridge);
 
-if (virFileWriteStr(field, "0", 0) < 0) {
+if (virFileWriteStr(accept_ra, "0", 0) < 0) {
 virReportSystemError(errno,
- _("cannot disable %s"), field);
+ _("cannot disable %s"), accept_ra);
 goto cleanup;
 }
-VIR_FREE(field);
 
 /* All interfaces used as a gateway (which is what this is, by
  * definition), must always have autoconf=0.
  */
-field = g_strdup_printf(SYSCTL_PATH "/net/ipv6/conf/%s/autoconf", 
def->bridge);
+autoconf = g_strdup_printf(SYSCTL_PATH "/net/ipv6/conf/%s/autoconf",
+   def->bridge);
 
-if (virFileWriteStr(field, "0", 0) < 0) {
+if (virFileWriteStr(autoconf, "0", 0) < 0) {
 virReportSystemError(errno,
- _("cannot disable %s"), field);
+ _("cannot disable %s"), autoconf);
 goto cleanup;
 }
 
 ret = 0;
  cleanup:
-VIR_FREE(field);
 return ret;
 }
 
-- 
2.25.4