In the quest to remove VLAs from the kernel[1], this adjusts the allocation of coefs and blocks to use the existing maximum values (with one new define, MAX_DISKS for coefs, and a reuse of the existing NDISKS for blocks). [1] https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Kyle Spiers <ksspiers@xxxxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> --- Switch from kmalloc() coefs and blocks to using maximum values --- crypto/async_tx/async_pq.c | 10 ++++++---- crypto/async_tx/raid6test.c | 4 +++- 2 files changed, 9 insertions(+), 5 deletions(-) diff --git a/crypto/async_tx/async_pq.c b/crypto/async_tx/async_pq.c index 56bd612927ab..80dc567801ec 100644 --- a/crypto/async_tx/async_pq.c +++ b/crypto/async_tx/async_pq.c @@ -42,6 +42,8 @@ static struct page *pq_scribble_page; #define P(b, d) (b[d-2]) #define Q(b, d) (b[d-1]) +#define MAX_DISKS 255 + /** * do_async_gen_syndrome - asynchronously calculate P and/or Q */ @@ -184,7 +186,7 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks, struct dma_device *device = chan ? chan->device : NULL; struct dmaengine_unmap_data *unmap = NULL; - BUG_ON(disks > 255 || !(P(blocks, disks) || Q(blocks, disks))); + BUG_ON(disks > MAX_DISKS || !(P(blocks, disks) || Q(blocks, disks))); if (device) unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOWAIT); @@ -196,7 +198,7 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks, is_dma_pq_aligned(device, offset, 0, len)) { struct dma_async_tx_descriptor *tx; enum dma_ctrl_flags dma_flags = 0; - unsigned char coefs[src_cnt]; + unsigned char coefs[MAX_DISKS]; int i, j; /* run the p+q asynchronously */ @@ -299,11 +301,11 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks, struct dma_chan *chan = pq_val_chan(submit, blocks, disks, len); struct dma_device *device = chan ? chan->device : NULL; struct dma_async_tx_descriptor *tx; - unsigned char coefs[disks-2]; + unsigned char coefs[MAX_DISKS]; enum dma_ctrl_flags dma_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0; struct dmaengine_unmap_data *unmap = NULL; - BUG_ON(disks < 4); + BUG_ON(disks < 4 || disks > MAX_DISKS); if (device) unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOWAIT); diff --git a/crypto/async_tx/raid6test.c b/crypto/async_tx/raid6test.c index dad95f45b88f..a5edaabae12a 100644 --- a/crypto/async_tx/raid6test.c +++ b/crypto/async_tx/raid6test.c @@ -81,11 +81,13 @@ static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, stru init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit); } else { - struct page *blocks[disks]; + struct page *blocks[NDISKS]; struct page *dest; int count = 0; int i; + BUG_ON(disks > NDISKS); + /* data+Q failure. Reconstruct data from P, * then rebuild syndrome */ -- 2.17.0.921.gf22659ad46-goog
