diff mbox series

[net,4/4] netfilter: nfnetlink_osf: fix possible bogus match in nf_osf_find()

Message ID 20220908095757.1755-5-fw@strlen.de (mailing list archive)
State Accepted
Commit 559c36c5a8d730c49ef805a72b213d3bba155cc8
Delegated to: Netdev Maintainers
Headers show
Series [net,1/4] netfilter: nf_conntrack_sip: fix ct_sip_walk_headers | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/subject_prefix success Link
netdev/cover_letter success Pull request is its own cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers fail 1 blamed authors not CCed: ffmancera@riseup.net; 3 maintainers not CCed: ffmancera@riseup.net coreteam@netfilter.org kadlec@netfilter.org
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 19 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Florian Westphal Sept. 8, 2022, 9:57 a.m. UTC 
From: Pablo Neira Ayuso <pablo@netfilter.org>

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>
---
 net/netfilter/nfnetlink_osf.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff mbox series

Patch

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);