From: Pablo Neira Ayuso pablo@netfilter.org
[ Upstream commit 559c36c5a8d730c49ef805a72b213d3bba155cc8 ]
nf_osf_find() incorrectly returns true on mismatch, this leads to copying uninitialized memory area in nft_osf which can be used to leak stale kernel stack data to userspace.
Fixes: 22c7652cdaa8 ("netfilter: nft_osf: Add version option support") Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Sasha Levin sashal@kernel.org --- net/netfilter/nfnetlink_osf.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/netfilter/nfnetlink_osf.c b/net/netfilter/nfnetlink_osf.c index 0fa2e2030427..ee6840bd5933 100644 --- a/net/netfilter/nfnetlink_osf.c +++ b/net/netfilter/nfnetlink_osf.c @@ -269,6 +269,7 @@ bool nf_osf_find(const struct sk_buff *skb, struct nf_osf_hdr_ctx ctx; const struct tcphdr *tcp; struct tcphdr _tcph; + bool found = false;
memset(&ctx, 0, sizeof(ctx));
@@ -283,10 +284,11 @@ bool nf_osf_find(const struct sk_buff *skb,
data->genre = f->genre; data->version = f->version; + found = true; break; }
- return true; + return found; } EXPORT_SYMBOL_GPL(nf_osf_find);