From 19a91dd4e39e755d650444da7f3a571b40a11093 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Fri, 23 Dec 2016 16:01:08 +0100 Subject: [PATCH] MMC: meson: avoid possible NULL dereference No actual segmentation faults were observed but the coding is at least inconsistent. irqreturn_t meson_mmc_irq(): We should not dereference host before checking it. meson_mmc_irq_thread(): If cmd or mrq are NULL we should not dereference them after writing a warning. Fixes: 51c5d8447bd7 MMC: meson: initial support for GX platforms Signed-off-by: Heinrich Schuchardt Acked-by: Kevin Hilman Signed-off-by: Ulf Hansson --- drivers/mmc/host/meson-gx-mmc.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c index b352760c041e..09739352834c 100644 --- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c @@ -578,13 +578,15 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id) { struct meson_host *host = dev_id; struct mmc_request *mrq; - struct mmc_command *cmd = host->cmd; + struct mmc_command *cmd; u32 irq_en, status, raw_status; irqreturn_t ret = IRQ_HANDLED; if (WARN_ON(!host)) return IRQ_NONE; + cmd = host->cmd; + mrq = host->mrq; if (WARN_ON(!mrq)) @@ -670,10 +672,10 @@ static irqreturn_t meson_mmc_irq_thread(int irq, void *dev_id) int ret = IRQ_HANDLED; if (WARN_ON(!mrq)) - ret = IRQ_NONE; + return IRQ_NONE; if (WARN_ON(!cmd)) - ret = IRQ_NONE; + return IRQ_NONE; data = cmd->data; if (data) { -- 2.20.1