[U-Boot] [PATCH] mmc: sdhci: fix NULL pointer access when host->ops is not set
Masahiro Yamada
yamada.masahiro at socionext.com
Fri Jan 13 03:51:51 CET 2017
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 <yamada.masahiro at socionext.com>
---
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 3a1f4f7..5b404ff 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 */
--
2.7.4
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