From: "Torne (Richard Coles)" <[email protected]> MMC CSD info can specify very large, ridiculous timeouts, big enough to overflow timeout_ns. This can result in the card timing out on every operation because the wrapped timeout value is far too small.
Fix the overflow by capping the result at UINT_MAX. Cards specifying longer timeouts are almost certainly insane, and host controllers generally cannot support timeouts that long in any case. Signed-off-by: Torne (Richard Coles) <[email protected]> --- drivers/mmc/core/core.c | 11 ++++++++++- 1 files changed, 10 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 0b6141d..74ec3d4 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -512,7 +512,16 @@ void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card) if (data->flags & MMC_DATA_WRITE) mult <<= card->csd.r2w_factor; - data->timeout_ns = card->csd.tacc_ns * mult; + /* + * The timeout in nanoseconds may overflow with some cards. Cap it at + * UINT_MAX to avoid the overflow; host controllers cannot generally + * generate timeouts that long anyway. + */ + if (card->csd.tacc_ns <= UINT_MAX / mult) + data->timeout_ns = card->csd.tacc_ns * mult; + else + data->timeout_ns = UINT_MAX; + data->timeout_clks = card->csd.tacc_clks * mult; /* -- 1.7.7.3 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
