From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 56F36392807; Sat, 12 Sep 2026 19:56:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789242984; cv=none; b=LM57fpIPIo/np+LR3QkFXP+qpCIK5UZZZCI8YOpDIMeB8IbT5MAA3/K+7uTfh9pTy2aSi3UWF+jWOvfaXjZmKUJ5trdHH0TDTkxYZuQTTlBqqJmBWMIAmJgdsvDexH/B9KYZK2+XbQjnHiyvB0x4a/aEB70DGe6LKlucdED41vg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789242984; c=relaxed/simple; bh=x3eCD5WtD3fhhBVvH7hhLVeoy4yL784+OZXJqpJ7THE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=dY/begPVBwuJQGuHHrSwoAHVL0H9MLTpzt2jOfKadEWLYQqlC72gv8msmiRFWSHwu0ka50g6ZwjayRrHiFYT2sve1XwGHkKHunyCr7spPy7D6jl5x7i3i706ASAm/lxJlRMYBUIgagVvXNm2MbMEJV75u0nBNukv7q445DEBfHg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zJQ4ArWG; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zJQ4ArWG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 69AB11F00893; Sat, 12 Sep 2026 19:56:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789242978; bh=SO0hK9T1JGZR4YuXbN4xqLbGB5t9kaOcKIwxgfokaOw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=zJQ4ArWGSfcVmIE1rSL8Okk7GMTExnC2p4E/YH4xzhoxAZNlK+up7pPeHoS1Iezui lG0roR/O0qCjeRnMNI0CpV75WV+c9S5ufunefG5YnqXExi9TY9b+UHhlL/5TxmLN5d YeA2YqLpZXDNLJyIT0RuCgGsffrs5J9D5f4upUsA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?R=C3=A9mi=20Denis-Courmont?= , Joe Damato , Stanislav Fomichev , Breno Leitao , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.10 593/798] phonet: pep: do not write beyond optlen in getsockopt Date: Sat, 12 Sep 2026 09:03:41 +0200 Message-ID: <20260912065530.717418567@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065516.948645775@linuxfoundation.org> References: <20260912065516.948645775@linuxfoundation.org> User-Agent: quilt/0.69 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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Breno Leitao [ Upstream commit 77e5eb0e192aec6710c03ca8144582fd2af36ca4 ] pep_getsockopt() clamps the reported length to the caller's buffer with min_t(), but then stores the value with put_user(val, (int __user *) optval), which always writes sizeof(int) bytes. A getsockopt() call with an optlen smaller than sizeof(int) thus reports the clamped length yet writes a full int, one to three bytes past the user buffer. Write the value with copy_to_user() bounded by len, so at most optlen bytes are copied, matching the length reported back to userspace. Fixes: 02a47617cdce ("Phonet: implement GPRS virtual interface over PEP socket") Acked-by: Rémi Denis-Courmont Reviewed-by: Joe Damato Acked-by: Stanislav Fomichev Signed-off-by: Breno Leitao Link: https://patch.msgid.link/20260729-getsockopt_phase4-v4-4-c44576757c17@debian.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/phonet/pep.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/phonet/pep.c b/net/phonet/pep.c index cac9631bd84ac..17f12911dba35 100644 --- a/net/phonet/pep.c +++ b/net/phonet/pep.c @@ -1093,7 +1093,7 @@ static int pep_getsockopt(struct sock *sk, int level, int optname, len = min_t(unsigned int, sizeof(int), len); if (put_user(len, optlen)) return -EFAULT; - if (put_user(val, (int __user *) optval)) + if (copy_to_user(optval, &val, len)) return -EFAULT; return 0; } -- 2.53.0