From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793212209; b=aiq/prv7yfo8FBGZwaGKeXnPfDsCKwwKl0Av21WV3FgCXR7tMXeyQzKGQdSWE8ETkCda xoj1FHne4fosxI+QtvLPCAxuv0PrwBoVJeFKoFdJP6KSo8SHPNuuAyUoZT46qUs7tY+32 3HEXFgx2UWk+wmFu2l9ew+GwNZAneD2jBBfIweDM+NemBrl8vEntVcyWeSrkE/CPtv6g5 7myEYBxsBPLGaZM4zpnLzsEJghMYcTzJOahRFYAd3z4GnBgF5sA5kxghNZhHHivuHiK9K MIq9m0nG4/BmGDuDlyLxk5vGJPU+NlPDUwjY7TjvNfzg2fAzy09knacNSkom8QHvpkQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793212209; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=s2eSCJ7SLow10u0YdapddpUVBPUUzT5zlOgYzvbw/dU=; b=AaFc7VSvzgBsmPLvJj3+3ii7hNEf+1762nDc+j7XSgQKD9cIi4xMK+SIEXWeoBgTn6wC hf2baBUTWqcpveB69rwvRJbqtb1ODvXG/0OCBFJZeawjiZR+kXNTxwxqasjN2lMIYAK57 oskKWtRU4i96h5o7kdqYbrGP1N3hreu6vV4CFB/F8aQ4NNMl7YJ6aBsrG2MlpusN+Z9OH AgCLiOnwZtAyBfyVeXbTHJDiidE0HRZbxV3BzKs31nS7tCmhNKRbgdrrOTpnuzxuqK91Y yiNug3E71/jqrmVURgEHaIaS00S6DV04KunkdLqwhHUcdPQs38vgKL5IE70+oBNoeCw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Kkwiphqs; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7346A606A31A; Wed, 28 Oct 2026 18:30:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Kkwiphqs Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D08D1F01825; Wed, 28 Oct 2026 18:30:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793212209; bh=s2eSCJ7SLow10u0YdapddpUVBPUUzT5zlOgYzvbw/dU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=KkwiphqsICuKFSDqPnLfsvNXK79gYZ1piczkSOHjH22bN7khVzZZSgihhS0bPBNLD higk7ewdCdpHKmA8cZnXWuP6IC7VIFM/XiN2DxnPqZH1RARLFRiG0/y6u81BnVuqJ/ BQa2IK81NbxgSGCyEKZgL6Pv7OZhpnjoBUysqZfA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Luis Chamberlain , Kees Cook , Andy Shevchenko , Sasha Levin Subject: [PATCH 6.1 0077/1887] params: Do not go over the limit when getting the string length Date: Wed, 28 Oct 2026 17:36:13 +0100 Message-ID: <20261028170500.986159152@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Shevchenko [ Upstream commit fd0cd057a1b7351604daa6ffc91dfe28adf7225d ] We can use strnlen() even on early stages and it prevents from going over the string boundaries in case it's already too long. Reviewed-by: Luis Chamberlain Reviewed-by: Kees Cook Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20231120151419.1661807-3-andriy.shevchenko@linux.intel.com Signed-off-by: Kees Cook Stable-dep-of: 3dfaae04243c ("params: fix charp corruption on allocation failure") Signed-off-by: Sasha Levin --- kernel/params.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/params.c b/kernel/params.c index e6df4c2ef097c..89c139e861faf 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -264,7 +264,10 @@ EXPORT_SYMBOL_GPL(param_set_uint_minmax); int param_set_charp(const char *val, const struct kernel_param *kp) { - if (strlen(val) > 1024) { + size_t len, maxlen = 1024; + + len = strnlen(val, maxlen + 1); + if (len == maxlen + 1) { pr_err("%s: string parameter too long\n", kp->name); return -ENOSPC; } @@ -274,7 +277,7 @@ int param_set_charp(const char *val, const struct kernel_param *kp) /* This is a hack. We can't kmalloc in early boot, and we * don't need to; this mangled commandline is preserved. */ if (slab_is_available()) { - *(char **)kp->arg = kmalloc_parameter(strlen(val)+1); + *(char **)kp->arg = kmalloc_parameter(len + 1); if (!*(char **)kp->arg) return -ENOMEM; strcpy(*(char **)kp->arg, val); @@ -512,7 +515,7 @@ int param_set_copystring(const char *val, const struct kernel_param *kp) { const struct kparam_string *kps = kp->str; - if (strlen(val)+1 > kps->maxlen) { + if (strnlen(val, kps->maxlen) == kps->maxlen) { pr_err("%s: string doesn't fit in %u chars.\n", kp->name, kps->maxlen-1); return -ENOSPC; -- 2.53.0