diff options
| author | Chris Ball <cjb@laptop.org> | 2012-11-05 14:29:49 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-11-17 13:16:33 -0800 |
| commit | f1e729c67400d3a766befa6f739f971021788878 (patch) | |
| tree | a46f6d8035fac8ed418b3ffcd3f39740789cb860 /drivers | |
| parent | c4cbedfda2227df82126c9dd5e7593565bf45d21 (diff) | |
mmc: sdhci: fix NULL dereference in sdhci_request() tuning
commit 14efd957209461bbdf285bf0d67e931955d04a4c upstream.
Commit 473b095a72a9 ("mmc: sdhci: fix incorrect command used in tuning")
introduced a NULL dereference at resume-time if an SD 3.0 host controller
raises the SDHCI_NEEDS_TUNING flag while no card is inserted. Seen on an
OLPC XO-4 with sdhci-pxav3, but presumably affects other controllers too.
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mmc/host/sdhci.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 3c403aa8495..1fe0ca9c10a 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1294,16 +1294,19 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq) */ if ((host->flags & SDHCI_NEEDS_RETUNING) && !(present_state & (SDHCI_DOING_WRITE | SDHCI_DOING_READ))) { - /* eMMC uses cmd21 while sd and sdio use cmd19 */ - tuning_opcode = mmc->card->type == MMC_TYPE_MMC ? - MMC_SEND_TUNING_BLOCK_HS200 : - MMC_SEND_TUNING_BLOCK; - spin_unlock_irqrestore(&host->lock, flags); - sdhci_execute_tuning(mmc, tuning_opcode); - spin_lock_irqsave(&host->lock, flags); - - /* Restore original mmc_request structure */ - host->mrq = mrq; + if (mmc->card) { + /* eMMC uses cmd21 but sd and sdio use cmd19 */ + tuning_opcode = + mmc->card->type == MMC_TYPE_MMC ? + MMC_SEND_TUNING_BLOCK_HS200 : + MMC_SEND_TUNING_BLOCK; + spin_unlock_irqrestore(&host->lock, flags); + sdhci_execute_tuning(mmc, tuning_opcode); + spin_lock_irqsave(&host->lock, flags); + + /* Restore original mmc_request structure */ + host->mrq = mrq; + } } if (mrq->sbc && !(host->flags & SDHCI_AUTO_CMD23)) |