clkdiv is declared as an u32 but it can be set to a negative value causing a huge divisor value. Change its type to int to avoid this case. Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # 3.4 and later --- drivers/mmc/host/atmel-mci.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 03d7c75..9a39e0b 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -1304,7 +1304,7 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) if (ios->clock) { unsigned int clock_min = ~0U; - u32 clkdiv; + int clkdiv; spin_lock_bh(&host->lock); if (!host->mode_reg) { @@ -1328,7 +1328,12 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) /* Calculate clock divider */ if (host->caps.has_odd_clk_div) { clkdiv = DIV_ROUND_UP(host->bus_hz, clock_min) - 2; - if (clkdiv > 511) { + if (clkdiv < 0) { + dev_warn(&mmc->class_dev, + "clock %u too fast; using %lu\n", + clock_min, host->bus_hz / 2); + clkdiv = 0; + } else if (clkdiv > 511) { dev_warn(&mmc->class_dev, "clock %u too slow; using %lu\n", clock_min, host->bus_hz / (511 + 2)); -- 2.2.0 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html