GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-06-27 09:02:06 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

dma-direct: always leak memory that can't be re-encrypted

Browse source 
[ Upstream commit a90cf30437 ]

We must never let unencrypted memory go back into the general page pool.
So if we fail to set it back to encrypted when freeing DMA memory, leak
the memory instead and warn the user.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Christoph Hellwig 2021-11-09 15:41:01 +01:00 • committed by Justin Hammond
parent b9a6c0a28e
commit e8f52d94ba
1 changed files with 10 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

14
kernel/dma/direct.c
View file

@ -84,9 +84,14 @@ static int dma_set_decrypted(struct device *dev, void *vaddr, size_t size)
static int dma_set_encrypted(struct device *dev, void *vaddr, size_t size)
{
int ret;
if (!force_dma_unencrypted(dev))
return 0;
return set_memory_encrypted((unsigned long)vaddr, 1 << get_order(size));
ret = set_memory_encrypted((unsigned long)vaddr, 1 << get_order(size));
if (ret)
pr_warn_ratelimited("leaking DMA memory that can't be re-encrypted\n");
return ret;
}
static void __dma_direct_free_pages(struct device *dev, struct page *page,
@ -273,7 +278,6 @@ done:
return ret;
out_encrypt_pages:
/* If memory cannot be re-encrypted, it must be leaked */
if (dma_set_encrypted(dev, page_address(page), size))
return NULL;
out_free_pages:
@ -319,7 +323,8 @@ void dma_direct_free(struct device *dev, size_t size,
} else {
if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
arch_dma_clear_uncached(cpu_addr, size);
dma_set_encrypted(dev, cpu_addr, 1 << page_order);
if (dma_set_encrypted(dev, cpu_addr, 1 << page_order))
return;
}
__dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
@ -363,7 +368,8 @@ void dma_direct_free_pages(struct device *dev, size_t size,
dma_free_from_pool(dev, vaddr, size))
return;
dma_set_encrypted(dev, vaddr, 1 << page_order);
if (dma_set_encrypted(dev, vaddr, 1 << page_order))
return;
__dma_direct_free_pages(dev, page, size);
}