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 97EF452E07B for ; Wed, 9 Sep 2026 23:46:06 +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=1788997567; cv=none; b=t/cjQGHCQwPhAAaj2AwK+RZcSfsH8Q96MkC1rNlxuT0IUNHOUayPi0TkretIxSafEYeTOi6QgZtLwqgien/JiOLkQq1VpLtKFqgN5bFm+6f8lflyWCtAijBiaBm40lxHuf6YsEsLBoBN0peWFAYyHtxwxnNtyEtBxGQz57qDBio= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788997567; c=relaxed/simple; bh=cfbPPQaGeBftXALrNlksr1YbyenAFqfYCzjzPv06G3k=; h=Date:To:From:Subject:Message-Id; b=rnrhXTF7GH+sqxeotyt/lxHQDi3/jxwb8rxbYTzUBfmo5fVWGQ79OVd21SOuegfiPawnOjsoIqZxIZDPQSWvPtEzHKtQGTFLtkfZeF4oD2lFXSExDy1KEpEUo6KmutfnjCfQOWmLmk0ygVFcF09nuYkZJ+yJbi1PtvnLyzXOuS0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=DJkDcNAd; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="DJkDcNAd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B83A1F000FF; Wed, 9 Sep 2026 23:46:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1788997566; bh=g9RIaZA2gDZfwTBoZjzz/rMt18ASvDP6V6WzoFDjG1w=; h=Date:To:From:Subject; b=DJkDcNAdRVohZa79oPR0IOcBlafl+XFUOXwaTWntKFUz1vJj8gmDMlv5hwi/nYIbT 5td9lmov5vyxwEeilB83sujNZHiliGpTcD7cC7fxgk6A1JFwwLsZ9yCM1mUYi1XMU6 kTKZXNPqh428Yzrb/cvYaZv8AFdHfV/h8p4S4P6M= Date: Wed, 09 Sep 2026 16:46:05 -0700 To: mm-commits@vger.kernel.org,ekffu200098@gmail.com,mhiramat@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: + bootconfig-skip-internal-tree-sanity-checks-in-kernel.patch added to mm-nonmm-unstable branch Message-Id: <20260909234606.0B83A1F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: bootconfig: skip internal tree sanity checks in kernel has been added to the -mm mm-nonmm-unstable branch. Its filename is bootconfig-skip-internal-tree-sanity-checks-in-kernel.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/bootconfig-skip-internal-tree-sanity-checks-in-kernel.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: Masami Hiramatsu (Google) Subject: bootconfig: skip internal tree sanity checks in kernel Date: Thu, 10 Sep 2026 00:54:02 +0900 In xbc_verify_tree(), the loop iterating through all nodes to check that xbc_nodes[i].next < xbc_node_num and xbc_nodes[i].child < xbc_node_num is a defensive sanity check against implementation regressions (such an out-of-bounds index cannot be produced by malformed input). Running this check in the kernel adds unnecessary boot-time overhead. Split this check out into xbc_sanity_check_tree() for userspace, so that it continues to run during userspace bootconfig validation (e.g. when applying or testing bootconfig with tools/bootconfig), but is omitted in the kernel to speed up initialization. Link: https://lore.kernel.org/178896924262.177508.71609739247457811.stgit@devnote2 Signed-off-by: Masami Hiramatsu (Google) Reported-by: Sang-Heon Jeon Closes: https://lore.kernel.org/all/20260905141637.1547429-1-ekffu200098@gmail.com/ Signed-off-by: Andrew Morton --- lib/bootconfig.c | 38 ++++++++++++++++++++++++++------------ 1 file changed, 26 insertions(+), 12 deletions(-) --- a/lib/bootconfig.c~bootconfig-skip-internal-tree-sanity-checks-in-kernel +++ a/lib/bootconfig.c @@ -1003,9 +1003,30 @@ static int __init xbc_close_brace(char * return __xbc_close_brace(n - 1); } +#ifndef __KERNEL__ +/* Sanity check for regression: node indices must be within bounds */ +static int __init xbc_sanity_check_tree(void) +{ + int i; + + for (i = 0; i < xbc_node_num; i++) { + if (xbc_nodes[i].next >= xbc_node_num) { + return xbc_parse_error("No closing brace", + xbc_node_get_data(xbc_nodes + i)); + } + if (xbc_nodes[i].child >= xbc_node_num) { + return xbc_parse_error("Broken child node", + xbc_node_get_data(xbc_nodes + i)); + } + } + + return 0; +} +#endif + static int __init xbc_verify_tree(void) { - int i, depth; + int depth; size_t len, wlen; struct xbc_node *n, *m; @@ -1022,17 +1043,6 @@ static int __init xbc_verify_tree(void) return -ENOENT; } - for (i = 0; i < xbc_node_num; i++) { - if (xbc_nodes[i].next >= xbc_node_num) { - return xbc_parse_error("No closing brace", - xbc_node_get_data(xbc_nodes + i)); - } - if (xbc_nodes[i].child >= xbc_node_num) { - return xbc_parse_error("Broken child node", - xbc_node_get_data(xbc_nodes + i)); - } - } - /* Key tree limitation check */ n = &xbc_nodes[0]; depth = 1; @@ -1203,6 +1213,10 @@ int __init xbc_init(const char *data, si ret = xbc_parse_tree(); if (!ret) ret = xbc_verify_tree(); +#ifndef __KERNEL__ + if (!ret) + ret = xbc_sanity_check_tree(); +#endif if (ret < 0) { if (epos) _ Patches currently in -mm which might be from mhiramat@kernel.org are bootconfig-reject-unexpected-data-after-null-character.patch tools-bootconfig-consolidate-xbc_init-to-error-message-wrapper.patch bootconfig-skip-internal-tree-sanity-checks-in-kernel.patch