 ab396eb03f
			
		
	
	
	ab396eb03f
	
	
	
		
			
			The unwind loop iterates down to -1 instead of stopping at 0 and ends up accessing ->frags[-1]. Signed-off-by: Dimitris Michailidis <dm@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
			66 lines
		
	
	
	
		
			1.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			66 lines
		
	
	
	
		
			1.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /* skb_dma_map.c: DMA mapping helpers for socket buffers.
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|  *
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|  * Copyright (C) David S. Miller <davem@davemloft.net>
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/module.h>
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| #include <linux/dma-mapping.h>
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| #include <linux/skbuff.h>
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| 
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| int skb_dma_map(struct device *dev, struct sk_buff *skb,
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| 		enum dma_data_direction dir)
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| {
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| 	struct skb_shared_info *sp = skb_shinfo(skb);
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| 	dma_addr_t map;
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| 	int i;
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| 
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| 	map = dma_map_single(dev, skb->data,
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| 			     skb_headlen(skb), dir);
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| 	if (dma_mapping_error(dev, map))
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| 		goto out_err;
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| 
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| 	sp->dma_maps[0] = map;
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| 	for (i = 0; i < sp->nr_frags; i++) {
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| 		skb_frag_t *fp = &sp->frags[i];
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| 
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| 		map = dma_map_page(dev, fp->page, fp->page_offset,
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| 				   fp->size, dir);
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| 		if (dma_mapping_error(dev, map))
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| 			goto unwind;
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| 		sp->dma_maps[i + 1] = map;
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| 	}
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| 	sp->num_dma_maps = i + 1;
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| 
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| 	return 0;
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| 
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| unwind:
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| 	while (--i >= 0) {
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| 		skb_frag_t *fp = &sp->frags[i];
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| 
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| 		dma_unmap_page(dev, sp->dma_maps[i + 1],
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| 			       fp->size, dir);
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| 	}
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| 	dma_unmap_single(dev, sp->dma_maps[0],
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| 			 skb_headlen(skb), dir);
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| out_err:
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| 	return -ENOMEM;
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| }
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| EXPORT_SYMBOL(skb_dma_map);
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| 
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| void skb_dma_unmap(struct device *dev, struct sk_buff *skb,
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| 		   enum dma_data_direction dir)
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| {
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| 	struct skb_shared_info *sp = skb_shinfo(skb);
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| 	int i;
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| 
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| 	dma_unmap_single(dev, sp->dma_maps[0],
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| 			 skb_headlen(skb), dir);
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| 	for (i = 0; i < sp->nr_frags; i++) {
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| 		skb_frag_t *fp = &sp->frags[i];
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| 
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| 		dma_unmap_page(dev, sp->dma_maps[i + 1],
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| 			       fp->size, dir);
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| 	}
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| }
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| EXPORT_SYMBOL(skb_dma_unmap);
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