From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Currently dma_resv_get_fences() will leak the previously allocated array if the fence iteration got restarted and the krealloc_array() fails. Free the old array by hand, and make sure we still clear the returned *fences so the caller won't end up accessing freed memory. Some (but not all) of the callers of dma_resv_get_fences() seem to still trawl through the array even when dma_resv_get_fences() failed. And let's zero out *num_fences as well for good measure. Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx> Cc: Christian König <christian.koenig@xxxxxxx> Cc: linux-media@xxxxxxxxxxxxxxx Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx Cc: linaro-mm-sig@xxxxxxxxxxxxxxxx Fixes: d3c80698c9f5 ("dma-buf: use new iterator in dma_resv_get_fences v3") Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> --- drivers/dma-buf/dma-resv.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index b6f71eb00866..38b4110378de 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -571,6 +571,7 @@ int dma_resv_get_fences(struct dma_resv *obj, enum dma_resv_usage usage, dma_resv_for_each_fence_unlocked(&cursor, fence) { if (dma_resv_iter_is_restarted(&cursor)) { + struct dma_fence **new_fences; unsigned int count; while (*num_fences) @@ -579,13 +580,17 @@ int dma_resv_get_fences(struct dma_resv *obj, enum dma_resv_usage usage, count = cursor.num_fences + 1; /* Eventually re-allocate the array */ - *fences = krealloc_array(*fences, count, - sizeof(void *), - GFP_KERNEL); - if (count && !*fences) { + new_fences = krealloc_array(*fences, count, + sizeof(void *), + GFP_KERNEL); + if (count && !new_fences) { + kfree(*fences); + *fences = NULL; + *num_fences = 0; dma_resv_iter_end(&cursor); return -ENOMEM; } + *fences = new_fences; } (*fences)[(*num_fences)++] = dma_fence_get(fence); -- 2.39.3