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 1B870509F0E; Wed, 30 Sep 2026 15:47:51 +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=1790783275; cv=none; b=ITmMmug/VR0Ab/9YWSq752BJkc61gJ83A5mefZUxPw+QGsPLvyJ2qX8FmpQMBwA9ASlp3W0C6uizC0HmqZOcZDMWt/cqjXvhmzrz9PSQacG7PZF/MSC+dH1axG5HphEmEFWYEEljJIno/JXjYesHrRnjd1OyT/f5uxMlr8sfD8o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790783275; c=relaxed/simple; bh=6ACNR0SeioMVlm8PipGj8O+7qPWaOkUw4oJU42BSEY8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qDiBbgaogelw18Kw81FWCUHoaX1Svx0Itp/VBjfzulprAye00YDw+eF4ItI66jY6knlLEfilREuK7RbTBp2G7oisXDSORjzjHLmFebASrsiOygYXzR+TmT9R/Gfp1p5QfubOhV/dsEBeIIEWuEdhge5MW/WjB/bGaedons6ctWI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=N8mCxlGK; 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="N8mCxlGK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BDFE51F00893; Wed, 30 Sep 2026 15:47:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790783268; bh=ZcwCnTKHhDEzqO49J7LyL4sXsYf+JSCvgVVM44pvCYE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=N8mCxlGKFpifi8jhTeraUpbER964vRHuQhEOBYlSKr5X9PfGVrbiuTfxOKFYjJmlP GGUoAkFpDdGpT5BHgb1LRNd4j8aGOn/yl56Awwf7ZyEoHETCxYYh/hnU82uhKZL3xI kko0145M/QMuxsMvla0DfUNSMlX9vzCe6J1fth8A= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Guangguan Wang , Wen Gu , "D. Wythe" , "David S. Miller" , Junjie Cao , Sasha Levin Subject: [PATCH 5.10 338/595] net/smc: check smcd_v2_ext_offset when receiving proposal msg Date: Wed, 30 Sep 2026 17:23:51 +0200 Message-ID: <20260930152354.949478725@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152347.700140858@linuxfoundation.org> References: <20260930152347.700140858@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-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guangguan Wang commit 9ab332deb671d8f7e66d82a2ff2b3f715bc3a4ad upstream. When receiving proposal msg in server, the field smcd_v2_ext_offset in proposal msg is from the remote client and can not be fully trusted. Once the value of smcd_v2_ext_offset exceed the max value, there has the chance to access wrong address, and crash may happen. This patch checks the value of smcd_v2_ext_offset before using it. Fixes: 5c21c4ccafe8 ("net/smc: determine accepted ISM devices") Signed-off-by: Guangguan Wang Reviewed-by: Wen Gu Reviewed-by: D. Wythe Signed-off-by: David S. Miller [ jcao: drop the af_smc.c hunk, the !smcd_v2_ext test already there covers it; result matches the 5.15.y backport a36364d8d4fab ] Signed-off-by: Junjie Cao Signed-off-by: Sasha Levin --- net/smc/smc_clc.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h index a57a3489df4ae..f7f656b297f9c 100644 --- a/net/smc/smc_clc.h +++ b/net/smc/smc_clc.h @@ -306,9 +306,15 @@ smc_get_clc_v2_ext(struct smc_clc_msg_proposal *prop) static inline struct smc_clc_smcd_v2_extension * smc_get_clc_smcd_v2_ext(struct smc_clc_v2_extension *prop_v2ext) { + u16 max_offset = offsetof(struct smc_clc_msg_proposal_area, pclc_smcd_v2_ext) - + offsetof(struct smc_clc_msg_proposal_area, pclc_v2_ext) - + offsetof(struct smc_clc_v2_extension, hdr) - + offsetofend(struct smc_clnt_opts_area_hdr, smcd_v2_ext_offset); + if (!prop_v2ext) return NULL; - if (!ntohs(prop_v2ext->hdr.smcd_v2_ext_offset)) + if (!ntohs(prop_v2ext->hdr.smcd_v2_ext_offset) || + ntohs(prop_v2ext->hdr.smcd_v2_ext_offset) > max_offset) return NULL; return (struct smc_clc_smcd_v2_extension *) -- 2.53.0