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 6BACC1C290; Mon, 15 Jan 2024 23:27:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Hmh40ORZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D4AAC433C7; Mon, 15 Jan 2024 23:27:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705361244; bh=gWVu0DGyxjlmkVChVPoGAddpi9m+zYf8NRgtJQVpRo8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Hmh40ORZZpGpoORDB80DGQBqFmHL4VYy+zUD/wCsd8o12Xl9NhNmKunXd6Pq2HTC7 4hFvBEivSGZHMjhwnVoK2v6kWyYAeM/OdSWrxtnB+WbRMwQjYaJdUKkhXdF9s8ryg+ 12fnTRvx3KKan7OMfCiQG9vSUIOCHqxVAp1Mom0uaB770ee0aiHrjhlk3hXCCRYeKC tt+9AswSKVHlXdxPz/dwGzzbboAo2aWQho3/cuYk4IbWtC9PVrQDNDllcrbWST4BRq L5XbfuuIq7XWP2U7kDYBn9xlBOS0uAzKBkMYimHqucsUgNaxBlL/TRs9bO9RCyyUOl M07PHu7R0VVvg== 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 5.15 02/12] powerpc/mm: Fix null-pointer dereference in pgtable_cache_add Date: Mon, 15 Jan 2024 18:26:47 -0500 Message-ID: <20240115232718.209642-2-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240115232718.209642-1-sashal@kernel.org> References: <20240115232718.209642-1-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 5.15.147 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 3a82f89827a5..4bc8f0c893a2 100644 --- a/arch/powerpc/mm/init-common.c +++ b/arch/powerpc/mm/init-common.c @@ -105,7 +105,7 @@ void pgtable_cache_add(unsigned int shift) * 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 @@ -118,7 +118,8 @@ void pgtable_cache_add(unsigned int shift) 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(shift)); + if (name) + new = kmem_cache_create(name, table_size, align, 0, ctor(shift)); if (!new) panic("Could not allocate pgtable cache for order %d", shift); -- 2.43.0