| Message ID | 20241115220202.31086-1-antonio@mandelbit.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | spi-imx: prevent overflow when estimating transfer time | expand |
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 0b6b0151b3a3..eeb7d082c247 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -1685,7 +1685,7 @@ static unsigned int spi_imx_transfer_estimate_time_us(struct spi_transfer *trans words = DIV_ROUND_UP(transfer->len * BITS_PER_BYTE, transfer->bits_per_word); word_delay_us = DIV_ROUND_CLOSEST(spi_delay_to_ns(&transfer->word_delay, transfer), NSEC_PER_USEC); - result += words * word_delay_us; + result += (u64)words * word_delay_us; } return min(result, U32_MAX);
The words delay is computed by multiplying two unsigned ints and by adding up the result to a u64 variable. The multiplication, however, is performed with 32bit math thus losing data when the actual result is larger than UINT32_MAX. Fix the operation by casting the first operand to u64, thus forcing the multiplication to be performed with 64bit math. This fixes 1 OVERFLOW_BEFORE_WIDEN issue reported by Coverity Report: CID 1601859: Integer handling issues (OVERFLOW_BEFORE_WIDEN) Cc: Mark Brown <broonie@kernel.org> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: imx@lists.linux.dev Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Antonio Quartulli <antonio@mandelbit.com> --- drivers/spi/spi-imx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)