netdev - [PATCH] nfx: llcp: fix possible use of uninitialized variable in nfc_llcp_send

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20230513114938.179085-1-krzysztof.kozlowski@linaro.org>
Date: Sat, 13 May 2023 13:49:38 +0200
From: Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To: Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>,
	Samuel Ortiz <sameo@...ux.intel.com>,
	Thierry Escande <thierry.escande@...labora.com>,
	netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] nfx: llcp: fix possible use of uninitialized variable in nfc_llcp_send_connect()

If sock->service_name is NULL, the local variable
service_name_tlv_length will not be assigned by nfc_llcp_build_tlv(),
later leading to using value frmo the stack.  Smatch warning:

  net/nfc/llcp_commands.c:442 nfc_llcp_send_connect() error: uninitialized symbol 'service_name_tlv_length'.

Fixes: de9e5aeb4f40 ("NFC: llcp: Fix usage of llcp_add_tlv()")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
---
 net/nfc/llcp_commands.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/nfc/llcp_commands.c b/net/nfc/llcp_commands.c
index 41e3a20c8935..cdb001de0692 100644
--- a/net/nfc/llcp_commands.c
+++ b/net/nfc/llcp_commands.c
@@ -390,7 +390,8 @@ int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
 	const u8 *service_name_tlv = NULL;
 	const u8 *miux_tlv = NULL;
 	const u8 *rw_tlv = NULL;
-	u8 service_name_tlv_length, miux_tlv_length,  rw_tlv_length, rw;
+	u8 service_name_tlv_length = 0;
+	u8 miux_tlv_length,  rw_tlv_length, rw;
 	int err;
 	u16 size = 0;
 	__be16 miux;
-- 
2.34.1