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 370002836B4; Mon, 5 May 2025 23:10:36 +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=1746486637; cv=none; b=HYmyXxGYJiBxvnKRdQATXckOX1EuM7stDmL++XJMkrSSzlfhGUt6kj4ixHiZ6CKSJRku0L/wNt2amxsALXNmsfKcdv5G8EG8tB9ufZK0uOQNhjWwl3IZcpkSUyZHhDNtpmDe2t0zNGuCm5V/Z00D4c08Vab4H7EXc6uqQOK7ehE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746486637; c=relaxed/simple; bh=V12DuPXNiRtWtQMzLPiLVqjBMCfbPhgvcS4XmvFCYQs=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=lP3izxvKKOVwihg+U3vG9tePYtc8AZIgyb4cXkx9L+JG3FMHP9PFsgKn7bpBykVxaf7uPmBtIC2iU/abcn9Xz0kZPweIqWzc4qOKIJo37pAFxBl6SCyBHip8hKBh/1NwMGuWcE6p+rtzawKakoiPn7dZ22+ZgQ1X2nQXv1UYnDM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bPj8J++W; 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="bPj8J++W" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16FFEC4CEE4; Mon, 5 May 2025 23:10:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746486636; bh=V12DuPXNiRtWtQMzLPiLVqjBMCfbPhgvcS4XmvFCYQs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bPj8J++WWS6XGeL+TP2GgHiU+eQihBeEfVuFRp90uubztY+HE4BCvbUUSkM0tRXEt P00GkYmQfhbHJeyF+GHxtKSD9bniUqVU5PD2xuOiyL/T1KA+IMMaF9RGuJewSlOsrq /w0y+rp3Bed8/dSrh0DQ9Rqd3F0QXjEahXsZbv4TA0nRrpgbNDhH2FrYlt5jnn2yuu Kfy5rdBtnOGIYmKEUt5C7QtwAZOrkRjmz38uYtITP2HkIfx6eEAnlhQvRpRN9CEP5E +9ZSNzDwoXaoMaZFCyAztlwbhlgrf2VYO+Wj+f6P5LfZJRH+vA/QBr3S4vLGulwDm0 VQjaquL0FNRXQ== 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 6.1 128/212] libbpf: Fix out-of-bound read Date: Mon, 5 May 2025 19:05:00 -0400 Message-Id: <20250505230624.2692522-128-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505230624.2692522-1-sashal@kernel.org> References: <20250505230624.2692522-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.1.136 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 a0fb50718daef..98d5e566e0582 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1751,7 +1751,7 @@ 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