From: Namjae Jeon <namjae.jeon@xxxxxxxxxxx> https://lkml.org/lkml/2013/4/1/292 As per above discussion, there is possibility that request's __data_len field may overflow when max_discard_sectors greater than UINT_MAX >> 9 If multiple discard requests get merged, merged discard request's size exceeds 4GB, there is possibility that merged discard request's __data_len field may overflow. This patch fixes this issue. Reported-by: Max Filippov <jcmvbkbc@xxxxxxxxx> Signed-off-by: Namjae Jeon <namjae.jeon@xxxxxxxxxxx> Signed-off-by: Vivek Trivedi <t.vivek@xxxxxxxxxxx> Tested-by: Max Filippov <jcmvbkbc@xxxxxxxxx> --- drivers/mmc/card/queue.c | 2 +- drivers/mmc/core/core.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c index 9447a0e..54726b7 100644 --- a/drivers/mmc/card/queue.c +++ b/drivers/mmc/card/queue.c @@ -166,7 +166,7 @@ static void mmc_queue_setup_discard(struct request_queue *q, return; queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q); - q->limits.max_discard_sectors = max_discard; + blk_queue_max_discard_sectors(q, max_discard); if (card->erased_byte == 0 && !mmc_can_discard(card)) q->limits.discard_zeroes_data = 1; q->limits.discard_granularity = card->pref_erase << 9; diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 7b435a3..6ee530c 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -2058,7 +2058,7 @@ static unsigned int mmc_do_calc_max_discard(struct mmc_card *card, if (card->erase_shift) max_qty = UINT_MAX >> card->erase_shift; else if (mmc_card_sd(card)) - max_qty = UINT_MAX; + max_qty = UINT_MAX >> 9; else max_qty = UINT_MAX / card->erase_size; @@ -2100,7 +2100,7 @@ unsigned int mmc_calc_max_discard(struct mmc_card *card) unsigned int max_discard, max_trim; if (!host->max_discard_to) - return UINT_MAX; + return UINT_MAX >> 9; /* * Without erase_group_def set, MMC erase timeout depends on clock -- 1.7.9.5 -- 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
