[PATCH 02/13] wifi: brcmfmac: Match complete firmware capability names

[Michael Reeves via B4 Relay <devnull+michael.reeves077.gmail.com@kernel.org>]

From: Michael Reeves <michael.reeves077@gmail.com>

BCM4388 firmware advertises "hp2p" without advertising "p2p". Substring
matching incorrectly treats "hp2p" as P2P support, causing userspace to
attempt Wi-Fi Direct interface creation that the firmware rejects.

Match complete whitespace-separated capability names instead. Remove the
trailing-space workarounds for SAE and FBT and reserve a terminating
byte outside the firmware response buffer.

Fixes: ec64241c9fd2 ("brcmfmac: obtain feature info using 'cap' firmware command")
Signed-off-by: Michael Reeves <michael.reeves077@gmail.com>
---
 .../wireless/broadcom/brcm80211/brcmfmac/feature.c   | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/feature.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/feature.c
index cc19e5e7eb..a3c221117d 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/feature.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/feature.c
@@ -42,10 +42,10 @@ static const struct brcmf_feat_fwcap brcmf_fwcap_map[] = {
 	{ BRCMF_FEAT_MONITOR_FLAG, "rtap" },
 	{ BRCMF_FEAT_MONITOR_FMT_RADIOTAP, "rtap" },
 	{ BRCMF_FEAT_DOT11H, "802.11h" },
-	{ BRCMF_FEAT_SAE, "sae " },
+	{ BRCMF_FEAT_SAE, "sae" },
 	{ BRCMF_FEAT_FWAUTH, "idauth" },
 	{ BRCMF_FEAT_SAE_EXT, "sae_ext" },
-	{ BRCMF_FEAT_FBT, "fbt " },
+	{ BRCMF_FEAT_FBT, "fbt" },
 	{ BRCMF_FEAT_OKC, "okc" },
 };
 
@@ -230,11 +230,12 @@ static void brcmf_feat_iovar_data_set(struct brcmf_if *ifp,
 static void brcmf_feat_firmware_capabilities(struct brcmf_if *ifp)
 {
 	struct brcmf_pub *drvr = ifp->drvr;
-	char caps[MAX_CAPS_BUFFER_SIZE];
+	char caps[MAX_CAPS_BUFFER_SIZE + 1] = {};
+	char *cap, *next = caps;
 	enum brcmf_feat_id id;
 	int i, err;
 
-	err = brcmf_fil_iovar_data_get(ifp, "cap", caps, sizeof(caps));
+	err = brcmf_fil_iovar_data_get(ifp, "cap", caps, sizeof(caps) - 1);
 	if (err) {
 		bphy_err(drvr, "could not get firmware cap (%d)\n", err);
 		return;
@@ -242,12 +243,17 @@ static void brcmf_feat_firmware_capabilities(struct brcmf_if *ifp)
 
 	brcmf_dbg(INFO, "[ %s]\n", caps);
 
-	for (i = 0; i < ARRAY_SIZE(brcmf_fwcap_map); i++) {
-		if (strnstr(caps, brcmf_fwcap_map[i].fwcap_id, sizeof(caps))) {
+	while ((cap = strsep(&next, " \t\r\n")) != NULL) {
+		if (!*cap)
+			continue;
+
+		for (i = 0; i < ARRAY_SIZE(brcmf_fwcap_map); i++) {
+			if (strcmp(cap, brcmf_fwcap_map[i].fwcap_id))
+				continue;
 			id = brcmf_fwcap_map[i].feature;
 			brcmf_dbg(INFO, "enabling feature: %s\n",
 				  brcmf_feat_names[id]);
-			ifp->drvr->feat_flags |= BIT(id);
+			drvr->feat_flags |= BIT(id);
 		}
 	}
 }

-- 
2.55.0