From bf9c4d146467297771a0f60bdb897be38671dba7 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 13 Jan 2017 11:51:51 +0900 Subject: [PATCH] mmc: sdhci: fix NULL pointer access when host->ops is not set Until recently, sdhci_ops was used only for overriding IO accessors. (so, host->ops was not set by any drivers except bcm2835_sdhci.c) Now, we have more optional callbacks, get_cd, set_control_reg, and set_clock. However, the code if (host->ops->get_cd) host->ops->get_cd(host); ... expects host->ops is set for all drivers. Commit 5e96217f0434 ("mmc: pic32_sdhci: move the code to pic32_sdhci.c") and commit 62226b68631b ("mmc: sdhci: move the callback function into sdhci_ops") added sdhci_ops for pic32_sdhci.c and s5p_sdhci.c, but the other drivers still do not (need not) set host->ops because all callbacks in sdhci_ops are optional. host->ops must be checked to avoid the system crash caused by NULL pointer access. Signed-off-by: Masahiro Yamada --- drivers/mmc/sdhci.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index 3a1f4f758c..5b404ff4a3 100644 --- a/drivers/mmc/sdhci.c +++ b/drivers/mmc/sdhci.c @@ -359,7 +359,7 @@ static int sdhci_set_clock(struct mmc *mmc, unsigned int clock) div >>= 1; } - if (host->ops->set_clock) + if (host->ops && host->ops->set_clock) host->ops->set_clock(host, div); clk |= (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT; @@ -427,7 +427,7 @@ static int sdhci_set_ios(struct mmc *mmc) u32 ctrl; struct sdhci_host *host = mmc->priv; - if (host->ops->set_control_reg) + if (host->ops && host->ops->set_control_reg) host->ops->set_control_reg(host); if (mmc->clock != host->clock) @@ -480,7 +480,7 @@ static int sdhci_init(struct mmc *mmc) sdhci_set_power(host, fls(mmc->cfg->voltages) - 1); - if (host->ops->get_cd) + if (host->ops && host->ops->get_cd) host->ops->get_cd(host); /* Enable only interrupts served by the SD controller */ -- 2.25.1