[PATCH] net: ipconfig: Fix more use after free

From: Thierry Reding
Date: Tue Aug 16 2016 - 10:46:32 EST


From: Thierry Reding <treding@xxxxxxxxxx>

While commit 9c706a49d660 ("net: ipconfig: fix use after free") avoids
the use after free, the resulting code still ends up calling both the
ic_setup_if() and ic_setup_routes() after calling ic_close_devs(), and
access to the device is still required.

Move the call to ic_close_devs() to the very end of the function.

Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
This applies on top of next-20160816.

net/ipv4/ipconfig.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index 66c2fe602810..ba9cbeafbb2e 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -1530,12 +1530,14 @@ static int __init ip_auto_config(void)
* 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;
+ err = -1;
+ else
+ err = 0;

+ ic_close_devs();

- return 0;
+ return err;
}

late_initcall(ip_auto_config);
--
2.9.0