From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from stravinsky.debian.org (stravinsky.debian.org [82.195.75.108]) (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 C0E3D4457DD; Wed, 29 Jul 2026 09:31:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.195.75.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785317490; cv=none; b=iRHaYB/4QuIE9WKjxizEc6I9JqFXVuYXTqg+2/eQ+mJ8RT1uA9CVXSRnnKSMZ3jE0OmIyOarHFLBzW+S39hyYsjea/CCeHMmbD1iNT9+ssxmYU0MTt+n/EY/oBRcs49zNvC1gpo1ge5y0ODZTzBw2ZLk1gTxozjga8MJ+oTd2sw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785317490; c=relaxed/simple; bh=1NrNY+r4xYOGN0JH6XpA5g6ZxfNL4Eq/GaaITEQSorE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=lDZ4bcuVeZPfyhHDdFqEVem0UccPzVjMpDQ3URJU2E7CY4+jf+bNNehzSyvXin6yIjA+GtZXIac0VYZiOdndhvwPbmX66iObv0eUxz5GuvVZ1vm/rb+4uF3BelX9o3cFiB4uzHaEdq7KLfNJW2Oeafm6oGykuJqybtVKOrEwQt8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org; spf=pass smtp.mailfrom=debian.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b=elh0hd6E; arc=none smtp.client-ip=82.195.75.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=debian.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b="elh0hd6E" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:Cc:To:In-Reply-To:References: Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description; bh=1IKXkR5PsNTL+UNImRoKO6WL2KC3d6ptd0mnVVEqdyM=; b=elh0hd6EeWdHRjbOEOi3pMtvxu ZmGsrevSrHM0yB6Y8cbhYJZIgb0CanyrzpZF2mNHuSVsnWecbsPvkOoP8eKd/dBnvj9UvmdBXmLtU KrSg59726zIbDz/5lWZVsZO/LUIjrxyvtehXv5SCjMGssyrfSejS/eo67q7oi3A9BlJbzb+FePH9j faTzhZBlrUq7f1Q/90+WG3xTXvsuOqfnQljK+NytZYJcUvoERNCqTDNoWqF9qwjlhj07GtIzTMosg xEPlOo/K/LPsA7b5x308pLHKcG9IpqsQvgkeNFJQ9B7+BJXrMvNluElr0qHaah+n+rLMNK3g2xfMA 8BepTAyQ==; Received: from authenticated-user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.96) (envelope-from ) id 1wp0dE-008Lzu-1N; Wed, 29 Jul 2026 09:31:20 +0000 From: Breno Leitao Date: Wed, 29 Jul 2026 02:29:47 -0700 Subject: [PATCH net-next v4 4/7] phonet: pep: do not write beyond optlen in getsockopt Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Message-Id: <20260729-getsockopt_phase4-v4-4-c44576757c17@debian.org> References: <20260729-getsockopt_phase4-v4-0-c44576757c17@debian.org> In-Reply-To: <20260729-getsockopt_phase4-v4-0-c44576757c17@debian.org> To: sdf@fomichev.me, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Alexander Aring , Stefan Schmidt , Miquel Raynal , Remi Denis-Courmont , =?utf-8?q?R=C3=A9mi_Denis-Courmont?= , John Fastabend , Sabrina Dubroca , Shuah Khan Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-wpan@vger.kernel.org, linux-kselftest@vger.kernel.org, Breno Leitao , kernel-team@meta.com, =?utf-8?q?R=C3=A9mi_Denis-Courmont?= , Joe Damato X-Mailer: b4 0.16-dev-d5d98 X-Developer-Signature: v=1; a=openpgp-sha256; l=1312; i=leitao@debian.org; h=from:subject:message-id; bh=1NrNY+r4xYOGN0JH6XpA5g6ZxfNL4Eq/GaaITEQSorE=; b=owEBbQKS/ZANAwAIATWjk5/8eHdtAcsmYgBqachLKdQH3psU5OQXQp0lqKvbk0MDseLj5VEvU /fLm9Jwf6SJAjMEAAEIAB0WIQSshTmm6PRnAspKQ5s1o5Of/Hh3bQUCamnISwAKCRA1o5Of/Hh3 bVYbD/49L0epPgbeGjS0lUIAKN5hqsjFZgBUwth28jh0U+8KmdW/f/C1W+zW5lnESfIDOSfwVVv J3BWE20wRZzMQ7RFuXOgRSIv0OAKJze5fF8bHOdiIelUg9rPoe4/7UAXKfbJVCZLeb1URVLjbbY yT+L2PEYITRMt/FGuf7RTXB6QN3Nrbt0Pfjuo75FVYNaIlJeIUXp3DGrp3Z6tFk8f5q+3syStlN tt3GZ0dJHalC96+rcq/Imge321qJwc0xI0sJzsy881isZ5kHlOa07akqGGoAHT2V65lUdeXcHhB Wr5bSW1cLS7YeRYfBMEFR/LBxCnejBbe1uMcWxtXg8HQ9JxqQqGVdvlykeA4tU41Ia9yl2vBaDJ y+kAJZNvyHAS9B887dEpTZbXPMDWQAFciJ2uG4dnFRV1+Noj7NRiErJFKMcq8W2a/mvPF/UTRKx eECrUFNAay049GUGLLWrOq8wWywh+iSWyaBl7BDkbTN+yevHIFBmZ7UnWdf5Cwsw0R5M8+NR0Ol 6T5YZYJ5HNGKihg1vhUA1ArEYAiJcjgF9l5g1Ry6F+qt6Fqcfo7kgyruVqgUdCLJmHnTPDn9IQq lqLZihM49vsJLFURA5Z16HOKXc22FbETc0r4+LTTjwG9VVDV+Jts3qdU/thd4h9qecqP+BgFl4g IeOEhPi2mNrX5fg== X-Developer-Key: i=leitao@debian.org; a=openpgp; fpr=AC8539A6E8F46702CA4A439B35A3939FFC78776D X-Debian-User: leitao 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 --- 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 7069271393933..60d1a5375725b 100644 --- a/net/phonet/pep.c +++ b/net/phonet/pep.c @@ -1115,7 +1115,7 @@ 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-Meta