netdev - [PATCH net-next] nfc: Remove checks for nla

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Message-Id: <20250617-nfc-null-data-v1-1-c7525ead2e95@kernel.org>
Date: Tue, 17 Jun 2025 09:45:39 +0100
From: Simon Horman <horms@...nel.org>
To: Krzysztof Kozlowski <krzk@...nel.org>
Cc: "David S. Miller" <davem@...emloft.net>, 
 Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>, 
 Paolo Abeni <pabeni@...hat.com>, netdev@...r.kernel.org, 
 Simon Horman <horms@...nel.org>
Subject: [PATCH net-next] nfc: Remove checks for nla_data returning NULL

The implementation of nla_data is as follows:

static inline void *nla_data(const struct nlattr *nla)
{
	return (char *) nla + NLA_HDRLEN;
}

Excluding the case where nla is exactly -NLA_HDRLEN, it will not return
NULL. And it seems misleading to assume that it can, other than in this
corner case. So drop checks for this condition.

Flagged by Smatch.

Compile tested only.

Signed-off-by: Simon Horman <horms@...nel.org>
---
 net/nfc/netlink.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index 6a40b8d0350d..a18e2c503da6 100644
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -1192,7 +1192,7 @@ static int nfc_genl_llc_sdreq(struct sk_buff *skb, struct genl_info *info)
 			continue;

 		uri = nla_data(sdp_attrs[NFC_SDP_ATTR_URI]);
-		if (uri == NULL || *uri == 0)
+		if (*uri == 0)
 			continue;

 		tid = local->sdreq_next_tid++;
@@ -1540,10 +1540,6 @@ static int nfc_genl_se_io(struct sk_buff *skb, struct genl_info *info)
 	}

 	apdu = nla_data(info->attrs[NFC_ATTR_SE_APDU]);
-	if (!apdu) {
-		rc = -EINVAL;
-		goto put_dev;
-	}

 	ctx = kzalloc(sizeof(struct se_io_ctx), GFP_KERNEL);
 	if (!ctx) {