[PATCH 4.12 065/106] wireless: wext: terminate ifr name coming from userspace
From: Greg Kroah-Hartman
Date: Wed Aug 09 2017 - 13:06:23 EST
4.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: "Levin, Alexander" <alexander.levin@xxxxxxxxxxx>
[ Upstream commit 98de4e0ea47d106846fc0e30ce4e644283fa7fc2 ]
ifr name is assumed to be a valid string by the kernel, but nothing
was forcing username to pass a valid string.
In turn, this would cause panics as we tried to access the string
past it's valid memory.
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/core/dev_ioctl.c | 2 ++
1 file changed, 2 insertions(+)
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -423,6 +423,8 @@ int dev_ioctl(struct net *net, unsigned
if (copy_from_user(&iwr, arg, sizeof(iwr)))
return -EFAULT;
+ iwr.ifr_name[sizeof(iwr.ifr_name) - 1] = 0;
+
return wext_handle_ioctl(net, &iwr, cmd, arg);
}