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 EC7B738F182; Mon, 5 May 2025 23:02:05 +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=1746486126; cv=none; b=FV4ooqN1/f9/ecR2wJWPC699SaVhjtSHWtAb7PDcWyTh7QOcZJWnE44aNvDQ8bwOfJVx74C5o08qElKpG+HB61UkR+cGp8oem4+wW0bFYOO8jhDemYVSKTIH5UAT1AjPQ4dK6RfJeD7Rt+R/LA/bWU83LhDrdHu++6VBdO+KPfA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746486126; c=relaxed/simple; bh=ZZUXIkOSS3hS2GknXyh0OcagJMVn6bqVb1rlYQfWut0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=e7H79piIDDbvRSYLE7AaUoeyrkYdX5NjDIFU3UfYbWyjbzTnWm4lsq1YzfOhg5hCQAzEEvowiXhTbtOfh6u5GzeR/RCW34nZ8vdKKSJcW3g8sjhhbg+gFz7XJYxGcwByVeSJzdcViiYrqp81JnfnU4XzrlPwG+RA1popVyvJTv4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=FeY061rg; 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="FeY061rg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D44A7C4CEF1; Mon, 5 May 2025 23:02:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746486125; bh=ZZUXIkOSS3hS2GknXyh0OcagJMVn6bqVb1rlYQfWut0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FeY061rg9/17Q27YvTvw2WzTt3ycF2HxCqhupfheopEJyS02coRmcT6f5EgFEJXsd CXYF0G5YfxQVmcEq9b3d0aJVz9wa5BAY4geJbLbUdCikxC0Q52sVnB2IljFisrrOxp Kw0ON0yY04z5JxEHDpVNuIWFoRtgItOuQmNq8Fsm0zny8Nwu45hs6VYlw1EZLDcUPN NU3yXRbTxrsYXdOFxkDQLCzCRxzzbMfoWztxU7Pi+JIJM7BoX3zIYuSD89SZbqMq35 ZJ6X19TFMFUEeX3LZ4tviqW6yPWoOPHsxynKEJBiSn9WiIRSCfSJ7sDhCp3/StOayQ hMT7FF95MxeQw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Nandakumar Edamana , Andrii Nakryiko , Sasha Levin , ast@kernel.org, daniel@iogearbox.net, eddyz87@gmail.com, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 6.6 165/294] libbpf: Fix out-of-bound read Date: Mon, 5 May 2025 18:54:25 -0400 Message-Id: <20250505225634.2688578-165-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505225634.2688578-1-sashal@kernel.org> References: <20250505225634.2688578-1-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 6.6.89 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 2fad178949efe..fa2abe56e845d 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1802,7 +1802,7 @@ 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