[NETFILTER]: Fix rcu race in ipt_REDIRECT Signed-off-by: Patrick McHardy --- commit 9af9e2ec732d00e62b458b46829bc696987d68af tree 71ec0256101fad8d11b6aaec8330fc1845ba9a23 parent 32be69721bfef1f0ab1c271c60002b06f27bf589 author Patrick McHardy Sat, 10 Sep 2005 17:48:21 +0200 committer Patrick McHardy Sat, 10 Sep 2005 17:48:21 +0200 net/ipv4/netfilter/ipt_REDIRECT.c | 16 ++++++++++------ 1 files changed, 10 insertions(+), 6 deletions(-) diff --git a/net/ipv4/netfilter/ipt_REDIRECT.c b/net/ipv4/netfilter/ipt_REDIRECT.c --- a/net/ipv4/netfilter/ipt_REDIRECT.c +++ b/net/ipv4/netfilter/ipt_REDIRECT.c @@ -88,14 +88,18 @@ redirect_target(struct sk_buff **pskb, newdst = htonl(0x7F000001); else { struct in_device *indev; + struct in_ifaddr *ifa; - /* Device might not have an associated in_device. */ - indev = (struct in_device *)(*pskb)->dev->ip_ptr; - if (indev == NULL || indev->ifa_list == NULL) - return NF_DROP; + newdst = 0; + + rcu_read_lock(); + indev = __in_dev_get((*pskb)->dev); + if (indev && (ifa = indev->ifa_list)) + newdst = ifa->ifa_local; + rcu_read_unlock(); - /* Grab first address on interface. */ - newdst = indev->ifa_list->ifa_local; + if (!newdst) + return NF_DROP; } /* Transfer from original range. */