linux-kernel - [PATCH] swiotlb: check alloc_size before the allocation of a new memory pool

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240108140005.3355316-1-zhangpeng362@huawei.com>
Date: Mon, 8 Jan 2024 22:00:05 +0800
From: Peng Zhang <zhangpeng362@...wei.com>
To: <hch@....de>, <m.szyprowski@...sung.com>, <robin.murphy@....com>,
	<petr.tesarik1@...wei-partners.com>, <iommu@...ts.linux.dev>,
	<linux-kernel@...r.kernel.org>
CC: <wangkefeng.wang@...wei.com>, <sunnanyong@...wei.com>,
	<zhangpeng362@...wei.com>
Subject: [PATCH] swiotlb: check alloc_size before the allocation of a new memory pool

From: ZhangPeng <zhangpeng362@...wei.com>

The allocation request for swiotlb contiguous memory greater than
128*2KB cannot be fulfilled because it exceeds the maximum contiguous
memory limit. If the swiotlb memory we allocate is larger than 128*2KB,
swiotlb_find_slots() will still schedule the allocation of a new memory
pool, which will increase memory overhead.

Fix it by adding a check with alloc_size no more than 128*2KB before
scheduling the allocation of a new memory pool in swiotlb_find_slots().

Signed-off-by: ZhangPeng <zhangpeng362@...wei.com>
---
 kernel/dma/swiotlb.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 33d942615be5..cc92cff02c60 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -1126,6 +1126,9 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
 	u64 phys_limit;
 	int index;
 
+	if (alloc_size > IO_TLB_SEGSIZE * IO_TLB_SIZE)
+		return -1;
+
 	rcu_read_lock();
 	list_for_each_entry_rcu(pool, &mem->pools, node) {
 		index = swiotlb_pool_find_slots(dev, pool, orig_addr,
-- 
2.25.1