4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> commit 2420489bcb8910188578acc0c11c75445c2e4b92 upstream. On the DMA mapping error path, sg may be NULL (it has already been marked as the last scatterlist entry), and we should avoid dereferencing it again. Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Fixes: e227330223a7 ("drm/i915: avoid leaking DMA mappings") Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Imre Deak <imre.deak@xxxxxxxxx> Link: http://patchwork.freedesktop.org/patch/msgid/20161114112930.2033-1-chris@xxxxxxxxxxxxxxxxxx Reviewed-by: Matthew Auld <matthew.auld@xxxxxxxxx> (cherry picked from commit b17993b7b29612369270567643bcff814f4b3d7f) Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/i915_gem.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2540,7 +2540,7 @@ i915_gem_object_get_pages_gtt(struct drm page = shmem_read_mapping_page(mapping, i); if (IS_ERR(page)) { ret = PTR_ERR(page); - goto err_pages; + goto err_sg; } } #ifdef CONFIG_SWIOTLB @@ -2583,8 +2583,9 @@ i915_gem_object_get_pages_gtt(struct drm return 0; -err_pages: +err_sg: sg_mark_end(sg); +err_pages: for_each_sgt_page(page, sgt_iter, st) put_page(page); sg_free_table(st); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html