From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 0F36428A1E8; Mon, 5 May 2025 22:28:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746484081; cv=none; b=vFr+hg4MaZSfmOJrIy2lGdkjMiOuQIzEtQ01pdIfvkg2lQTORV4Iiitloswwdsg4VqaHyzcLEjHBh8ow/e//7N1mWYiWevr677kdUBPUB0zuoqgILZGepeL2MIsU3II8lM3GLPhdCsPVbsMYUbYlgGfMkQ49ZvQSEbOlC78Sxb4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746484081; c=relaxed/simple; bh=wttWyXaQxRhpbHgkxP0KWBPlqCAEhUh8aI7oF4j4C88=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=fJjLYAkxcFo48PEP4g8KerZsVftyBoUfbTbgUjEPBZcOTSpglJJB1GcfUrSK6Am9ON1gq0cLig8G7iO4m32MW2UOva2OeYztHhffcKgDKn7B5eZ8IzTWHTQms/C01+rG/JWT6pkydW9pGdGi0DeDtwY19NxOGfoJbBXHj/Msktg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rjVdFHkB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rjVdFHkB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8C08FC4CEED; Mon, 5 May 2025 22:27:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746484080; bh=wttWyXaQxRhpbHgkxP0KWBPlqCAEhUh8aI7oF4j4C88=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rjVdFHkB+xHwQgBkY+1CSP+lW0Bncd4Oub8L8hOA+d0UdxcSPeN52Ba8cuKICkx6T Tkyb+MvNH5hknhX4d2Y+DQTTeHB/LOIC6b0TwSIlrAzQjz2wqU3I5oubA0fijMiseS d5tw2WZQGzYxJDdGuUQdKft4WoUxG2Ict87a8mXFKaJwtkEkCwAoRrUXc16IWR1g9Q IraGF5ayMYZzLXkkk9rkST0baOepoJNOZ1nncawcZnukokbJJ5ZlT3SU1KybLVAlXK 1GUvM3IuVQ/ozyAZxv1vRU5feb7BkyiLh5cl9nSCtmMqrh6jIw+gJ7wft2jlysKEg9 GK6dO6EMkEpuQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Nandakumar Edamana , Andrii Nakryiko , Sasha Levin , eddyz87@gmail.com, ast@kernel.org, daniel@iogearbox.net, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 6.14 339/642] libbpf: Fix out-of-bound read Date: Mon, 5 May 2025 18:09:15 -0400 Message-Id: <20250505221419.2672473-339-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505221419.2672473-1-sashal@kernel.org> References: <20250505221419.2672473-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.14.5 Content-Transfer-Encoding: 8bit From: Nandakumar Edamana [ Upstream commit 236d3910117e9f97ebf75e511d8bcc950f1a4e5f ] In `set_kcfg_value_str`, an untrusted string is accessed with the assumption that it will be at least two characters long due to the presence of checks for opening and closing quotes. But the check for the closing quote (value[len - 1] != '"') misses the fact that it could be checking the opening quote itself in case of an invalid input that consists of just the opening quote. This commit adds an explicit check to make sure the string is at least two characters long. Signed-off-by: Nandakumar Edamana Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20250221210110.3182084-1-nandakumar@nandakumar.co.in Signed-off-by: Sasha Levin --- tools/lib/bpf/libbpf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 6b436ec872b0f..1791a12b1aac5 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2106,7 +2106,7 @@ static int set_kcfg_value_str(struct extern_desc *ext, char *ext_val, } len = strlen(value); - if (value[len - 1] != '"') { + if (len < 2 || value[len - 1] != '"') { pr_warn("extern (kcfg) '%s': invalid string config '%s'\n", ext->name, value); return -EINVAL; -- 2.39.5