[PATCH v3 -next 1/9] DMA, CMA: fix possible memory leak
From: Joonsoo Kim <hidden>
Date: 2014-06-16 05:36:46
Also in:
kvm, linux-arm-kernel, linux-mm, lkml
Subsystem:
driver core, kobjects, debugfs and sysfs, the rest · Maintainers:
Greg Kroah-Hartman, "Rafael J. Wysocki", Danilo Krummrich, Linus Torvalds
We should free memory for bitmap when we find zone mis-match, otherwise this memory will leak. Additionally, I copy code comment from PPC KVM's CMA code to inform why we need to check zone mis-match. * Note Minchan suggested to add a tag for the stable, but, I don't do it, because I found this possibility during code-review and, IMO, this patch isn't suitable for stable tree. Acked-by: Zhang Yanfei <redacted> Reviewed-by: Michal Nazarewicz <redacted> Reviewed-by: Aneesh Kumar K.V <redacted> Signed-off-by: Joonsoo Kim <redacted>
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index 83969f8..6467c91 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c@@ -176,14 +176,24 @@ static int __init cma_activate_area(struct cma *cma) base_pfn = pfn; for (j = pageblock_nr_pages; j; --j, pfn++) { WARN_ON_ONCE(!pfn_valid(pfn)); + /* + * alloc_contig_range requires the pfn range + * specified to be in the same zone. Make this + * simple by forcing the entire CMA resv range + * to be in the same zone. + */ if (page_zone(pfn_to_page(pfn)) != zone) - return -EINVAL; + goto err; } init_cma_reserved_pageblock(pfn_to_page(base_pfn)); } while (--i); mutex_init(&cma->lock); return 0; + +err: + kfree(cma->bitmap); + return -EINVAL; } static struct cma cma_areas[MAX_CMA_AREAS];
--
1.7.9.5