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 E62F042CB17; Sat, 12 Sep 2026 10:40:29 +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=1789209631; cv=none; b=NgNl8iWf/gkqJip/WzcUU+2IK6V9+zqyVTx9x4xV2QAu2KHwPQ3Vk4byKUUqtYUJ5TVwEEhl2HJAy8yVxOLv0QDNS4byB94Zvczg5YNgUV5bQL3DhyiukJBPUp3YvC+lQPmOMnXZqlEQX9/aAZi6CWqqNfCxz4rRQeDLKvgOKxo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789209631; c=relaxed/simple; bh=ej3zmFYSgbf9akCiE6FMoMdADTtLyfzlnaMsOtiMkEk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=oU7sebqlob95dmfLuhH77jBLwBHRf0u9OxpFjfJRB+UVJ0C2/tqLmuJ539FqAXCZwad2BrAaq+Jw7VoakPxObJZNmieZtQ4oVRi1d7sUGA05uNEP6aU6gjRO+vzj9DBXRf68JiYLUS50Tlb2ba2J4Zcpa1mTPBNAkoAW59elzdI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iNUIMT6b; 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="iNUIMT6b" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C73341F00893; Sat, 12 Sep 2026 10:40:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789209629; bh=M7+3gmbNBknqSx9l7e0D8tdNfHWY/gyR6g9LYPy056E=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=iNUIMT6bJF9ZyPc4Y5YqGDmej1ga7G06FR+FG1a0Q2SSiATD1eEAqelsZiHWRuXVj TdJeVxJsIkZg19As6KA+OuflrYZ74ILgM8LhhK1rXAZ6ponsXIK8jm54dW5PhDCsAV i8RTrdNWz3EVPTtHa/PL22i27/wiREXCbxdk4EQg= 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 6.18 0859/1518] phonet: pep: do not write beyond optlen in getsockopt Date: Sat, 12 Sep 2026 08:50:28 +0200 Message-ID: <20260912065642.882020037@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065623.398859879@linuxfoundation.org> References: <20260912065623.398859879@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 6.18-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 5910dcd26555e..36c85811fd08b 100644 --- a/net/phonet/pep.c +++ b/net/phonet/pep.c @@ -1116,7 +1116,7 @@ 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