From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F248B22D8AC; Sun, 24 Nov 2024 13:48:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732456127; cv=none; b=hD2qMUZ49GEWUBJZCRdgum5MALqenhb4u/47yUZ5gEJFW47bgN+82NIx4XuNtjypo1ekB247k3mt/Ybs0UVMBNslLosBzslNT15xTFO2Je4mPoKDWeZ8VMdI/xzd3BkoyYnk36L64WiMHIXLrpPXIWJrKt2ejQyMYvOZGPa8www= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732456127; c=relaxed/simple; bh=bH8rF4pvqhkLX9MmqDxbmk8XE1OmQ3C9OYOXM8n5uiE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=M5v+SWoKKIm53edPi5Z8+BWv7g7Ie0hI9ZHt49MrOKOSEvR44sW3yZKgPBZTq758ATvbK+XFWHuOZxFkRnF33my00sY0oP7ML5Nzn/f/qkeBoYvYbm5QG4ZoQj8F6yCKVlU4MI8HniPSet6COCfQ5ux9FYXyC5K0vIiLG0haLB8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=osXcdr0I; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="osXcdr0I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1195DC4CED3; Sun, 24 Nov 2024 13:48:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1732456126; bh=bH8rF4pvqhkLX9MmqDxbmk8XE1OmQ3C9OYOXM8n5uiE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=osXcdr0IiLwap4GDLhfTeQQlPpnVx7F7JqxhIIGXLC6sZwCxTWi6n9fLtbZXoteAc 0R33labsaVRxjFvH7U1/QaWC9eeFB7Iiyo7BB8HwKna5/7J5skqERHxabcz7W/XHVm Rt1d9LTEwAEXnC5iocSRKar8neaQAJoso/kKFW4g+EfuS40Bpw2jc0e8ZNtQvFdp7v qWJE4ROaa/LqDUOruSLmQaLRRBAnLcOjxODKcEQaG4wh/pERsR6xoXoinVYS5YioEq RVsvpDZ2RtfCillzdycLyRdbJSsjyciKu6I9Zeqc66BbDP79l8XvK3x3r7YyzIYRXB wJeWd4uKgV+4g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Norbert van Bolhuis , Kalle Valo , Sasha Levin , arend.vanspriel@broadcom.com, ulf.hansson@linaro.org, sebastian.reichel@collabora.com, jacobe.zang@wesion.com, erick.archer@outlook.com, krzysztof.kozlowski@linaro.org, linux-wireless@vger.kernel.org, brcm80211@lists.linux.dev, brcm80211-dev-list.pdl@broadcom.com Subject: [PATCH AUTOSEL 6.6 50/61] wifi: brcmfmac: Fix oops due to NULL pointer dereference in brcmf_sdiod_sglist_rw() Date: Sun, 24 Nov 2024 08:45:25 -0500 Message-ID: <20241124134637.3346391-50-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241124134637.3346391-1-sashal@kernel.org> References: <20241124134637.3346391-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: brcm80211@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.63 Content-Transfer-Encoding: 8bit From: Norbert van Bolhuis [ Upstream commit 857282b819cbaa0675aaab1e7542e2c0579f52d7 ] This patch fixes a NULL pointer dereference bug in brcmfmac that occurs when a high 'sd_sgentry_align' value applies (e.g. 512) and a lot of queued SKBs are sent from the pkt queue. The problem is the number of entries in the pre-allocated sgtable, it is nents = max(rxglom_size, txglom_size) + max(rxglom_size, txglom_size) >> 4 + 1. Given the default [rt]xglom_size=32 it's actually 35 which is too small. Worst case, the pkt queue can end up with 64 SKBs. This occurs when a new SKB is added for each original SKB if tailroom isn't enough to hold tail_pad. At least one sg entry is needed for each SKB. So, eventually the "skb_queue_walk loop" in brcmf_sdiod_sglist_rw may run out of sg entries. This makes sg_next return NULL and this causes the oops. The patch sets nents to max(rxglom_size, txglom_size) * 2 to be able handle the worst-case. Btw. this requires only 64-35=29 * 16 (or 20 if CONFIG_NEED_SG_DMA_LENGTH) = 464 additional bytes of memory. Signed-off-by: Norbert van Bolhuis Signed-off-by: Kalle Valo Link: https://patch.msgid.link/20241107132903.13513-1-nvbolhuis@gmail.com Signed-off-by: Sasha Levin --- drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c index 00679a990e3da..7710367c319ec 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c @@ -770,7 +770,7 @@ void brcmf_sdiod_sgtable_alloc(struct brcmf_sdio_dev *sdiodev) nents = max_t(uint, BRCMF_DEFAULT_RXGLOM_SIZE, sdiodev->settings->bus.sdio.txglomsz); - nents += (nents >> 4) + 1; + nents *= 2; WARN_ON(nents > sdiodev->max_segment_count); -- 2.43.0