[PATCH 4.14 006/284] spi: Fix invalid sgs value

Greg Kroah-Hartman
2022-04-18T13:38:17Z

From: Biju Das <biju.das.jz@bp.renesas.com>

[ Upstream commit 1a4e53d2fc4f68aa654ad96d13ad042e1a8e8a7d ]

max_seg_size is unsigned int and it can have a value up to 2^32
(for eg:-RZ_DMAC driver sets dma_set_max_seg_size as U32_MAX)
When this value is used in min_t() as an integer type, it becomes
-1 and the value of sgs becomes 0.

Fix this issue by replacing the 'int' data type with 'unsigned int'
in min_t().

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20220307184843.9994-1-biju.das.jz@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/spi/spi.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 71f74015efb9..d26aefed16ac 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -774,10 +774,10 @@ static int spi_map_buf(struct spi_controller *ctlr, struct device *dev,
int i, ret;

if (vmalloced_buf || kmap_buf) {
- desc_len = min_t(int, max_seg_size, PAGE_SIZE);
+ desc_len = min_t(unsigned int, max_seg_size, PAGE_SIZE);
sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len);
} else if (virt_addr_valid(buf)) {
- desc_len = min_t(int, max_seg_size, ctlr->max_dma_len);
+ desc_len = min_t(unsigned int, max_seg_size, ctlr->max_dma_len);
sgs = DIV_ROUND_UP(len, desc_len);
} else {
return -EINVAL;
--
2.34.1