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 1b34d21..7f5cdc1 100644 (file)
--- 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))