From: Miles Chen <miles.chen@mediatek.com>
Date: Thu, 22 Feb 2018 11:22:20 +0000 (+0800)
Subject: dma-debug: fix memory leak in debug_dma_alloc_coherent
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=af1da686843750809738c01e153320106e890804;p=linux.git

dma-debug: fix memory leak in debug_dma_alloc_coherent

Marty reported a memory leakage introduced by commit 3aaabbf1c39e
("lib/dma-debug.c: fix incorrect pfn calculation"). Fix it
by checking the virtual address before allocating the entry.

This patch also use virt_addr_valid() instead of virt_to_page()
to check if a virtual address is linear.

Fixes: 3aaabbf1 ("lib/dma-debug.c: fix incorrect pfn calculation")
Reported-by: Marty Faltesek <mfaltesek@google.com>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---

diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index 1b34d210452c5..7f5cdc1e6b298 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -1491,12 +1491,12 @@ void debug_dma_alloc_coherent(struct device *dev, size_t size,
 	if (unlikely(virt == NULL))
 		return;
 
-	entry = dma_entry_alloc();
-	if (!entry)
+	/* handle vmalloc and linear addresses */
+	if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt))
 		return;
 
-	/* handle vmalloc and linear addresses */
-	if (!is_vmalloc_addr(virt) && !virt_to_page(virt))
+	entry = dma_entry_alloc();
+	if (!entry)
 		return;
 
 	entry->type      = dma_debug_coherent;
@@ -1528,7 +1528,7 @@ void debug_dma_free_coherent(struct device *dev, size_t size,
 	};
 
 	/* handle vmalloc and linear addresses */
-	if (!is_vmalloc_addr(virt) && !virt_to_page(virt))
+	if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt))
 		return;
 
 	if (is_vmalloc_addr(virt))