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 9C1112DECDF; Tue, 21 Jul 2026 18:11:13 +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=1784657474; cv=none; b=fnE709oMn6LEdLLikES8cJROTW0S+YhP2flAc48W0BgQdwillHV/M6bCtIVZbEYfr5WubDJ2s0HINXVK0de5EOAYSB2FaCk+0EdhUJo98y23URTuC+HExFlMEAeMx4ERvzEK639LrwDFmfwNhl7iIg8JzFKSdeJa/D51TGlr6yM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784657474; c=relaxed/simple; bh=XGWk+sbXG/PA/syq48tzQX4/qKlzkeoXHS0OZESKYC4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uJjc1WnecLRxv2PfZFUJaicmKM+67gLuVLtn1EBir4OWZFrJVLxfm0wgMU0y9kd8paJPq8kYM5/uzUFS+0Ixqv/un7bMjQ09Y5wmgBZEwUDc17H/aT4qCBVkBHVN5003r0VkU6yMPTqx3femBYDyqc8OJ52upr+82ZLw5+6Vabc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=GE6TjeuA; 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="GE6TjeuA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E4251F000E9; Tue, 21 Jul 2026 18:11:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784657473; bh=RcxRLLXeJJ/AAQYgwu3YjW165m+4r/IEvDrutapE73o=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=GE6TjeuApKoc+S1JljV36RPS9DuBBpEojpKtDtrJ+OTXazfjw8Ybte7gCgWS4g7G5 NtScL1emRhZ2Sy7M5kasWT9u/qHfH1VR+L1v6vzeEB0uN04qwBVFLn/O+9HRUjdQ8f N9Zv2xs/J1FWQsVfaTF4dBOgxz140upCVV4mjgXw= 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 6.18 0777/1611] perf tools: Use snprintf() for root_dir path construction Date: Tue, 21 Jul 2026 17:14:53 +0200 Message-ID: <20260721152532.864351809@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152514.750365251@linuxfoundation.org> References: <20260721152514.750365251@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 6.18-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 1de644fe91a873..50f5f2b2ae530c 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -1319,7 +1319,7 @@ 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 7535a78b7fd235..7d4c6d7cdc60d7 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -2166,7 +2166,7 @@ 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