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 6FDE125618; Mon, 15 Jan 2024 23:29:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tSLmZ9FW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7CC66C433C7; Mon, 15 Jan 2024 23:29:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705361378; bh=oEnldYYsyAuN3N3mFx4WkfY4z/2IXM/LPciKPtLBNSE=; h=From:To:Cc:Subject:Date:From; b=tSLmZ9FWIE5pht1drTUxMq8pbzjxdMHhwpTlY7SyrwRLMHDDDEJiWCdD8fntpwRUq cyUzJqDuSpS41u4mndXjFF+Ir0mRRulCgooj1BAMGloS6H3MZrBK5nK+q28ZBJdDsU UgHd/IMVb0IeQGYQIisO8ZypOWZwB+Z4brse7T9EHORwBrRo7GmRbEFWoq419ocgll Ml+DXsw5jKK0bWx0ANasckR0KztUyTGPxskZzqQww1n5H1O7S+m5Gi5y3PyYeOITLh xyR8F5Et80rekBORw7Zc/bQETT1fsth0Dy4n8gOUYtL6vOptpbxUXoPq861ddXsTvt I4vrcWGJiQPqA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Kunwu Chan , Christophe Leroy , Michael Ellerman , Sasha Levin , linuxppc-dev@lists.ozlabs.org Subject: [PATCH AUTOSEL 4.19 1/4] powerpc/mm: Fix null-pointer dereference in pgtable_cache_add Date: Mon, 15 Jan 2024 18:29:26 -0500 Message-ID: <20240115232935.210529-1-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 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 4.19.305 Content-Transfer-Encoding: 8bit From: Kunwu Chan [ Upstream commit f46c8a75263f97bda13c739ba1c90aced0d3b071 ] kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Ensure the allocation was successful by checking the pointer validity. Suggested-by: Christophe Leroy Suggested-by: Michael Ellerman Signed-off-by: Kunwu Chan Signed-off-by: Michael Ellerman Link: https://msgid.link/20231204023223.2447523-1-chentao@kylinos.cn Signed-off-by: Sasha Levin --- arch/powerpc/mm/init-common.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/mm/init-common.c b/arch/powerpc/mm/init-common.c index 2b656e67f2ea..927703af49be 100644 --- a/arch/powerpc/mm/init-common.c +++ b/arch/powerpc/mm/init-common.c @@ -65,7 +65,7 @@ void pgtable_cache_add(unsigned shift, void (*ctor)(void *)) * as to leave enough 0 bits in the address to contain it. */ unsigned long minalign = max(MAX_PGTABLE_INDEX_SIZE + 1, HUGEPD_SHIFT_MASK + 1); - struct kmem_cache *new; + struct kmem_cache *new = NULL; /* It would be nice if this was a BUILD_BUG_ON(), but at the * moment, gcc doesn't seem to recognize is_power_of_2 as a @@ -78,7 +78,8 @@ void pgtable_cache_add(unsigned shift, void (*ctor)(void *)) align = max_t(unsigned long, align, minalign); name = kasprintf(GFP_KERNEL, "pgtable-2^%d", shift); - new = kmem_cache_create(name, table_size, align, 0, ctor); + if (name) + new = kmem_cache_create(name, table_size, align, 0, ctor); if (!new) panic("Could not allocate pgtable cache for order %d", shift); -- 2.43.0