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 3BAD7199227; Thu, 6 Jun 2024 14:13:03 +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=1717683183; cv=none; b=YWpvI3JUJ5hGbSULcENBlRluBIpXyymI/rw2qRrl7avxm6H4phyzKrCI6bL7+f3FfmGDnGoLJV2Xy+i5apG6srvdmupzz4Xd6902m4fqzjnGT5kSivJzB6MljK/KkM3vfu8g+0yXc5Saz2KJQqixDu80T20Za7UQcWRhVV6vY+o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717683183; c=relaxed/simple; bh=E01z3fhCHeitaRIUKpI6cnZYtWVB1y/aOj2SRCu+eIo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=d+iMsEGyARvxwL2UtfCIGXoQIU1aIqJ/H4avrkBf3fcWIMuXzqfmgrekdDe2haODVVk0xZmUh3bHJuZmzzEVgAZak/LGT4GL82h0kdPAC0gLOylEWyxkY41VlgkacqNKX7pyLiqM6Mjn96ToOai6bP8XC7WfiQQcpSJRkFYpXGs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Lz7c6PBE; 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="Lz7c6PBE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16197C2BD10; Thu, 6 Jun 2024 14:13:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1717683183; bh=E01z3fhCHeitaRIUKpI6cnZYtWVB1y/aOj2SRCu+eIo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Lz7c6PBEydlyDNzbNUfv+wrS8gzomc08tyN2XVGCX8eALeEZo/TqVrwe53Fkffw6p 7VzzMafzqOGDmvDT2nyEWr7znP/jtbRxfBFUvkGLb0GJr6o9wEMheWr5+jb/1WJnjC peJScLpR2LC9IysP+U7IyVa68mVrHzIxUhS7tGMc= 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 6.6 127/744] wifi: brcmfmac: pcie: handle randbuf allocation failure Date: Thu, 6 Jun 2024 15:56:39 +0200 Message-ID: <20240606131736.496598363@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240606131732.440653204@linuxfoundation.org> References: <20240606131732.440653204@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-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 80220685f5e45..a43af82691401 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