__change_page_attr() can fail which will cause set_memory_encrypted() and
set_memory_decrypted() to return non-zero.
If the device requires unencrypted DMA memory and decryption fails, simply
free the memory and fail.
If attempting to re-encrypt in the failure path and that encryption fails,
there is no alternative other than to leak the memory.
Fixes:
c10f07aa27da ("dma/direct: Handle force decryption for DMA coherent buffers in common code")
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
{
struct page *page;
void *ret;
+ int err;
size = PAGE_ALIGN(size);
}
ret = page_address(page);
- if (force_dma_unencrypted(dev))
- set_memory_decrypted((unsigned long)ret, 1 << get_order(size));
+ if (force_dma_unencrypted(dev)) {
+ err = set_memory_decrypted((unsigned long)ret,
+ 1 << get_order(size));
+ if (err)
+ goto out_free_pages;
+ }
memset(ret, 0, size);
return ret;
out_encrypt_pages:
- if (force_dma_unencrypted(dev))
- set_memory_encrypted((unsigned long)page_address(page),
- 1 << get_order(size));
+ if (force_dma_unencrypted(dev)) {
+ err = set_memory_encrypted((unsigned long)page_address(page),
+ 1 << get_order(size));
+ /* If memory cannot be re-encrypted, it must be leaked */
+ if (err)
+ return NULL;
+ }
out_free_pages:
dma_free_contiguous(dev, page, size);
return NULL;