From: Robin Murphy <robin.murphy@arm.com>
To: akpm@linux-foundation.org, linux-kernel@vger.kernel.org
Cc: arnd@arndb.de, m.szyprowski@samsung.com, sumit.semwal@linaro.org,
sakari.ailus@iki.fi, linux-arch@vger.kernel.org,
linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org
Subject: [PATCH 1/4] dmapool: Fix overflow condition in pool_find_page
Date: Fri, 25 Sep 2015 13:15:43 +0100 [thread overview]
Message-ID: <be19713dc9e80c6486e86c60a43e149d45b104a3.1443178314.git.robin.murphy@arm.com> (raw)
In-Reply-To: <cover.1443178314.git.robin.murphy@arm.com>
If a DMA pool lies at the very top of the dma_addr_t range (as may
happen with an IOMMU involved), the calculated end address of the pool
wraps around to zero, and page lookup always fails. Tweak the relevant
calculation to be overflow-proof.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
mm/dmapool.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/dmapool.c b/mm/dmapool.c
index 71a8998..312a716 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -394,7 +394,7 @@ static struct dma_page *pool_find_page(struct dma_pool *pool, dma_addr_t dma)
list_for_each_entry(page, &pool->page_list, page_list) {
if (dma < page->dma)
continue;
- if (dma < (page->dma + pool->allocation))
+ if ((dma - page->dma) < pool->allocation)
return page;
}
return NULL;
--
1.9.1
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2015-09-25 12:15 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-25 12:15 [PATCH 0/4] Assorted DMA mapping tweaks Robin Murphy
2015-09-25 12:15 ` Robin Murphy [this message]
2015-09-25 12:15 ` [PATCH 2/4] dma-mapping: Tidy up dma_parms default handling Robin Murphy
2015-09-25 12:15 ` [PATCH 3/4] dma-debug: Check nents in dma_sync_sg* Robin Murphy
2015-09-25 12:15 ` [PATCH 4/4] dma-debug: Allow poisoning nonzero allocations Robin Murphy
2015-09-25 12:44 ` Russell King - ARM Linux
2015-09-25 17:35 ` Robin Murphy
2015-09-29 21:27 ` Andrew Morton
2015-10-07 19:17 ` Robin Murphy
2015-10-07 19:33 ` Andrew Morton
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=be19713dc9e80c6486e86c60a43e149d45b104a3.1443178314.git.robin.murphy@arm.com \
--to=robin.murphy@arm.com \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=m.szyprowski@samsung.com \
--cc=sakari.ailus@iki.fi \
--cc=sumit.semwal@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).