diff options
| author | Alex Mastro <amastro@fb.com> | 2025-11-25 17:11:18 -0800 |
|---|---|---|
| committer | Alex Williamson <alex@shazbot.org> | 2025-11-28 10:06:25 -0700 |
| commit | 590d745680309f8d956c3f0a97270fe65013b272 (patch) | |
| tree | 5d5d32974122de92e78da996135e6f43404edd43 | |
| parent | 98693e0897f754e3f51ce6626ed5f785f625ba2b (diff) | |
dma-buf: fix integer overflow in fill_sg_entry() for buffers >= 8GiB
fill_sg_entry() splits large DMA buffers into multiple scatter-gather
entries, each holding up to UINT_MAX bytes. When calculating the DMA
address for entries beyond the second one, the expression (i * UINT_MAX)
causes integer overflow due to 32-bit arithmetic.
This manifests when the input arg length >= 8 GiB results in looping for
i >= 2.
Fix by casting i to dma_addr_t before multiplication.
Fixes: 3aa31a8bb11e ("dma-buf: provide phys_vec to scatter-gather mapping routine")
Signed-off-by: Alex Mastro <amastro@fb.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Leon Romanovsky <leon@kernel.org>
Link: https://lore.kernel.org/r/20251125-dma-buf-overflow-v1-1-b70ea1e6c4ba@fb.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
| -rw-r--r-- | drivers/dma-buf/dma-buf-mapping.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/dma-buf/dma-buf-mapping.c b/drivers/dma-buf/dma-buf-mapping.c index b4819811a64a..b7352e609fbd 100644 --- a/drivers/dma-buf/dma-buf-mapping.c +++ b/drivers/dma-buf/dma-buf-mapping.c @@ -24,7 +24,7 @@ static struct scatterlist *fill_sg_entry(struct scatterlist *sgl, size_t length, * does not require the CPU list for mapping or unmapping. */ sg_set_page(sgl, NULL, 0, 0); - sg_dma_address(sgl) = addr + i * UINT_MAX; + sg_dma_address(sgl) = addr + (dma_addr_t)i * UINT_MAX; sg_dma_len(sgl) = len; sgl = sg_next(sgl); } |