Messages in this thread Patch in this message | | | From | Marek Szyprowski <> | Subject | [PATCH] spi: Ensure that sg_table won't be used after being freed | Date | Fri, 30 Sep 2022 13:34:08 +0200 |
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SPI code checks for non-zero sgt->orig_nents to determine if the buffer has been DMA-mapped. Ensure that sg_table is really zeroed after free to avoid potential NULL pointer dereference if the given SPI xfer object is reused again without being DMA-mapped.
Fixes: 0c17ba73c08f ("spi: Fix cache corruption due to DMA/PIO overlap") Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- drivers/spi/spi.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 44e4352d948b..5f9aedd1f0b6 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1102,6 +1102,8 @@ static void spi_unmap_buf_attrs(struct spi_controller *ctlr, if (sgt->orig_nents) { dma_unmap_sgtable(dev, sgt, dir, attrs); sg_free_table(sgt); + sgt->orig_nents = 0; + sgt->nents = 0; } } -- 2.17.1
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