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 D18D53C1098; Tue, 21 Jul 2026 21:31:44 +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=1784669505; cv=none; b=A0BuNTDnzMQxEc3HUQJWDItWAtbqvhSKxnTrbRthEalVEn5cf/XgfwH0ZJzRnJglsZLgVGMI/aMFD0wN6NRTv1D1F0Hwu1siUoiUKgb01EN76qjoa+DCGXjdliWVgwebJav/00deSz0OClf0HBtlsqQOqUpcIcvXby3c4BOgkcs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784669505; c=relaxed/simple; bh=x6nsc+yXtUJad3HH9b+9zTaosfLf0c9sWSGUlU1IssY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=u7mEKhCNJvmGVTNH8Y2/3vjEd1RlRQS3HVgfmVE/Qec5R8+omnpmDx0xsZ/CdD5NcEqiDPmn5JAsVdiMZFLZAF4n2BSdZGbz8U11p/Th6h5l9Tb0QSr6UZpww+lUqv2+cSh358+GE1206DWanEHJTyBkDhijMIxHuUOouIq2U7s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XPkOUWci; 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="XPkOUWci" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2DFA21F00A3F; Tue, 21 Jul 2026 21:31:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784669504; bh=EdCF8jVhhdhrMmJn8LlCbDoHPQHjIgvtPu4QtGAmQJE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=XPkOUWci2/245lwClrJ19jrg5WWTLxIptF8eKMudugbwM3GDTfLZJ7N5/pb77Ndn2 2y+l17RsPInRLwclOAb620riGcnzJUoMqBcmmBPTRG4JMBPOlJcCA+PqHqZqYih/7g rnMTRVUyP9JPUp/dbsvAD73djmQFcsSnx6r3uh1g= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, sashiko-bot , Zhang Yanmin , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 6.1 0563/1067] perf tools: Use snprintf() for root_dir path construction Date: Tue, 21 Jul 2026 17:19:24 +0200 Message-ID: <20260721152437.198405269@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152424.521567757@linuxfoundation.org> References: <20260721152424.521567757@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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnaldo Carvalho de Melo [ Upstream commit 7b0df6f4d498b1608afccfd6dffb264e6da91693 ] get_kernel_version() in machine.c and dso__load_guest_kernel_sym() in symbol.c use sprintf() to construct paths by prepending root_dir to "/proc/version" and "/proc/kallsyms" respectively. Both write into PATH_MAX stack buffers, but root_dir comes from --guestmount or KVM configuration and is not length-checked. A root_dir at or near PATH_MAX causes a stack buffer overflow. Switch to snprintf() with sizeof(path) to prevent overflow. Reported-by: sashiko-bot Fixes: a1645ce12adb6c9c ("perf: 'perf kvm' tool for monitoring guest performance from host") Cc: Zhang Yanmin Assisted-by: Claude:claude-opus-4.6 Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/util/machine.c | 2 +- tools/perf/util/symbol.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 9cd52f50ea7acf..419147da8d672b 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -1443,7 +1443,7 @@ static char *get_kernel_version(const char *root_dir) char *name, *tmp; const char *prefix = "Linux version "; - sprintf(version, "%s/proc/version", root_dir); + snprintf(version, sizeof(version), "%s/proc/version", root_dir); file = fopen(version, "r"); if (!file) return NULL; diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index b434f2398df5ac..bc79eace253591 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -2336,7 +2336,7 @@ static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map) if (!kallsyms_filename) return -1; } else { - sprintf(path, "%s/proc/kallsyms", machine->root_dir); + snprintf(path, sizeof(path), "%s/proc/kallsyms", machine->root_dir); kallsyms_filename = path; } -- 2.53.0