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 52E8715EFC3; Mon, 27 May 2024 19:23:55 +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=1716837835; cv=none; b=Qr1EfAsGOqVYkkw3lDLoMl8SZvXsVmQ/QufFDMogF06rzFx43F+Bq0Qx7kaq/SyjUQB7VNg53/SBKrsihzT9vzSm5N579PXTfzRc7Lgbqibo3jXmI/jWZcWl8laA1qfAcqyFOlcZRzJmf6oZZjfURUF/15Lg/5mAdo2o0YdYdCA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716837835; c=relaxed/simple; bh=beXH7DVFVzfU3oNGLok66jpL6CeNs0heUBSLX6MPFjU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=F5n1CRIFH9mUFRgmOt3e0Puog+H+9n85T5wdpxJ/8X/zcpyx2L8zzp1y4nOGf+BWjnaxH3GC1UFA0MLkrFR9jf9fy0kT3R52JiP/HBAG7mvszfm8BgUQ+cnG2i+UoFvIdua1fTRmjy5CQ1a5PBwVKg0Hj9+NFJBHgyVPa2Dv800= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0xsEaKB/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="0xsEaKB/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D93BBC32781; Mon, 27 May 2024 19:23:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1716837835; bh=beXH7DVFVzfU3oNGLok66jpL6CeNs0heUBSLX6MPFjU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0xsEaKB/Zbtef9hV5rZxK4pceOr0u0lt2qeI63l3IAixEQEYRXesNQTxDMr/vhy56 7pRa3zmZxOtdlZQ91Pk2avAIz0wgA4bLd/4ZCH8YbisQhHnd50oawgvgFtuqCJIqIr tMa5qUpseRuXn1X7Vrk7fTKa0h55tPDVca3IdHqg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Arnd Bergmann , Duoming Zhou , Kalle Valo , Sasha Levin Subject: [PATCH 6.8 162/493] wifi: brcmfmac: pcie: handle randbuf allocation failure Date: Mon, 27 May 2024 20:52:44 +0200 Message-ID: <20240527185635.681925213@linuxfoundation.org> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20240527185626.546110716@linuxfoundation.org> References: <20240527185626.546110716@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Duoming Zhou [ Upstream commit 316f790ebcf94bdf59f794b7cdea4068dc676d4c ] The kzalloc() in brcmf_pcie_download_fw_nvram() will return null if the physical memory has run out. As a result, if we use get_random_bytes() to generate random bytes in the randbuf, the null pointer dereference bug will happen. In order to prevent allocation failure, this patch adds a separate function using buffer on kernel stack to generate random bytes in the randbuf, which could prevent the kernel stack from overflow. Fixes: 91918ce88d9f ("wifi: brcmfmac: pcie: Provide a buffer of random bytes to the device") Suggested-by: Arnd Bergmann Signed-off-by: Duoming Zhou Signed-off-by: Kalle Valo Link: https://msgid.link/20240306140437.18177-1-duoming@zju.edu.cn Signed-off-by: Sasha Levin --- .../wireless/broadcom/brcm80211/brcmfmac/pcie.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c index d7fb88bb6ae1a..06698a714b523 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c @@ -1675,6 +1675,15 @@ struct brcmf_random_seed_footer { #define BRCMF_RANDOM_SEED_MAGIC 0xfeedc0de #define BRCMF_RANDOM_SEED_LENGTH 0x100 +static noinline_for_stack void +brcmf_pcie_provide_random_bytes(struct brcmf_pciedev_info *devinfo, u32 address) +{ + u8 randbuf[BRCMF_RANDOM_SEED_LENGTH]; + + get_random_bytes(randbuf, BRCMF_RANDOM_SEED_LENGTH); + memcpy_toio(devinfo->tcm + address, randbuf, BRCMF_RANDOM_SEED_LENGTH); +} + static int brcmf_pcie_download_fw_nvram(struct brcmf_pciedev_info *devinfo, const struct firmware *fw, void *nvram, u32 nvram_len) @@ -1717,7 +1726,6 @@ static int brcmf_pcie_download_fw_nvram(struct brcmf_pciedev_info *devinfo, .length = cpu_to_le32(rand_len), .magic = cpu_to_le32(BRCMF_RANDOM_SEED_MAGIC), }; - void *randbuf; /* Some Apple chips/firmwares expect a buffer of random * data to be present before NVRAM @@ -1729,10 +1737,7 @@ static int brcmf_pcie_download_fw_nvram(struct brcmf_pciedev_info *devinfo, sizeof(footer)); address -= rand_len; - randbuf = kzalloc(rand_len, GFP_KERNEL); - get_random_bytes(randbuf, rand_len); - memcpy_toio(devinfo->tcm + address, randbuf, rand_len); - kfree(randbuf); + brcmf_pcie_provide_random_bytes(devinfo, address); } } else { brcmf_dbg(PCIE, "No matching NVRAM file found %s\n", -- 2.43.0