net: ipconfig: fix use after free
ic_close_devs() calls kfree() for all devices's ic_device. Since commit
2647cffb2bc6 ("net: ipconfig: Support using "delayed" DHCP replies")
the active device's ic_device is still used however to print the
ipconfig summary which results in an oops if the memory is already
changed. So delay freeing until after the autoconfig results are
reported.
Fixes: 2647cffb2bc6 ("net: ipconfig: Support using "delayed" DHCP replies")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index 42cf629..66c2fe6 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -1493,14 +1493,6 @@
return -1;
/*
- * Close all network devices except the device we've
- * autoconfigured and set up routes.
- */
- ic_close_devs();
- if (ic_setup_if() < 0 || ic_setup_routes() < 0)
- return -1;
-
- /*
* Record which protocol was actually used.
*/
#ifdef IPCONFIG_DYNAMIC
@@ -1534,6 +1526,15 @@
pr_cont("\n");
#endif /* !SILENT */
+ /*
+ * Close all network devices except the device we've
+ * autoconfigured and set up routes.
+ */
+ ic_close_devs();
+ if (ic_setup_if() < 0 || ic_setup_routes() < 0)
+ return -1;
+
+
return 0;
}