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 7449724B2D; Mon, 15 Jan 2024 23:29:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RKwh/fmd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F6E9C433C7; Mon, 15 Jan 2024 23:29:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705361348; bh=HJ2dsFmXbbCVdzlJ3AIFBcn7PX2u0lXgIf8+eQxFgEw=; h=From:To:Cc:Subject:Date:From; b=RKwh/fmdxoBHjgYiK/hcNMUREVh1TULlPFGXwhT+3bhHYQXHSPwrXOjWz0pCn4prz QPZwTQfC/UuAuwMuEHfR/8sZY3OCYWm7mJwXN9ONnXAMWuQcIsgsxyLewDiJGwLtjG Byd/oILUB5V+P9VmubrhvovZvNL5uxohO1cyWxpJnPgrYYe0YH6GqhQPrlWiy+YNrt dMkSgOOzioEZw2H6PN8wn/Ej5oBBpQAwz6o0aytM7ztvFvlF/wfBR8aZhnTR19xXYe ttuz4GVgSWIK11GNtSVzybZbFIago4PG+d3V4Nak5PNuBowORENQaHV+/6FTOK7ICn /9yf/QiYu1A9Q== 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 5.4 1/7] powerpc/mm: Fix null-pointer dereference in pgtable_cache_add Date: Mon, 15 Jan 2024 18:28:46 -0500 Message-ID: <20240115232905.210324-1-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 5.4.267 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 a84da92920f7..e7b9cc90fd9e 100644 --- a/arch/powerpc/mm/init-common.c +++ b/arch/powerpc/mm/init-common.c @@ -104,7 +104,7 @@ 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 @@ -117,7 +117,8 @@ 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