[PATCH] nfc: llcp: fix sdreq TLV list leak on parse/alloc/send failure

[PATCH] nfc: llcp: fix sdreq TLV list leak on parse/alloc/send failure

[Cong Nguyen]

nfc_genl_llc_sdreq() builds a list of TLV nodes while walking nested
netlink attrs, but 3 error paths (nested-attr parse failure, TLV alloc
ENOMEM, nfc_llcp_send_snl_sdreq() failure) all skip freeing what was
already queued.

Route them through a new free_list label, mirroring the SDRES path in
the same file which already does this. Harmless on the success path
too -- send_snl_sdreq() drains the list as it moves nodes, so it's
already empty by the time free_list runs.

Fixes: d9b8d8e19b07 ("NFC: llcp: Service Name Lookup netlink interface")
Assisted-by: Claude:claude-opus-4
Signed-off-by: Cong Nguyen <congnt264@gmail.com>
---
 net/nfc/netlink.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index 0c58824cb150..224bdfa2dd0d 100644
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -1181,7 +1181,7 @@ static int nfc_genl_llc_sdreq(struct sk_buff *skb, struct genl_info *info)
 
 		if (rc != 0) {
 			rc = -EINVAL;
-			goto put_local;
+			goto free_list;
 		}
 
 		if (!sdp_attrs[NFC_SDP_ATTR_URI])
@@ -1200,7 +1200,7 @@ static int nfc_genl_llc_sdreq(struct sk_buff *skb, struct genl_info *info)
 		sdreq = nfc_llcp_build_sdreq_tlv(tid, uri, uri_len);
 		if (sdreq == NULL) {
 			rc = -ENOMEM;
-			goto put_local;
+			goto free_list;
 		}
 
 		tlvs_len += sdreq->tlv_len;
@@ -1215,6 +1215,9 @@ static int nfc_genl_llc_sdreq(struct sk_buff *skb, struct genl_info *info)
 
 	rc = nfc_llcp_send_snl_sdreq(local, &sdreq_list, tlvs_len);
 
+free_list:
+	nfc_llcp_free_sdp_tlv_list(&sdreq_list);
+
 put_local:
 	nfc_llcp_local_put(local);
 
-- 
2.25.1

Re: [PATCH] nfc: llcp: fix sdreq TLV list leak on parse/alloc/send failure

[Simon Horman]

On Mon, Sep 14, 2026 at 07:11:29PM +0700, Cong Nguyen wrote:
> nfc_genl_llc_sdreq() builds a list of TLV nodes while walking nested
> netlink attrs, but 3 error paths (nested-attr parse failure, TLV alloc
> ENOMEM, nfc_llcp_send_snl_sdreq() failure) all skip freeing what was
> already queued.
> 
> Route them through a new free_list label, mirroring the SDRES path in
> the same file which already does this. Harmless on the success path
> too -- send_snl_sdreq() drains the list as it moves nodes, so it's
> already empty by the time free_list runs.
> 
> Fixes: d9b8d8e19b07 ("NFC: llcp: Service Name Lookup netlink interface")
> Assisted-by: Claude:claude-opus-4
> Signed-off-by: Cong Nguyen <congnt264@gmail.com>

Reviewed-by: Simon Horman <horms@kernel.org>