| Message ID | 20220127071638.4057899-1-gregkh@linuxfoundation.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] moxart: fix potential use-after-free on remove path | expand |
On Thu, 27 Jan 2022 at 08:16, Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote: > > It was reported that the mmc host structure could be accessed after it > was freed in moxart_remove(), so fix this by saving the base register of > the device and using it instead of the pointer dereference. > > Cc: Ulf Hansson <ulf.hansson@linaro.org> > Cc: Xiyu Yang <xiyuyang19@fudan.edu.cn> > Cc: Xin Xiong <xiongx18@fudan.edu.cn> > Cc: Xin Tan <tanxin.ctf@gmail.com> > Cc: Tony Lindgren <tony@atomide.com> > Cc: Yang Li <yang.lee@linux.alibaba.com> > Cc: linux-mmc@vger.kernel.org > Cc: stable <stable@vger.kernel.org> > Reported-by: whitehat002 <hackyzh002@gmail.com> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Applied for fixes, thanks! Kind regards Uffe > --- > v2: changed to only move mmc_free_host() call as per Ulf's request > > drivers/mmc/host/moxart-mmc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c > index 16d1c7a43d33..b6eb75f4bbfc 100644 > --- a/drivers/mmc/host/moxart-mmc.c > +++ b/drivers/mmc/host/moxart-mmc.c > @@ -705,12 +705,12 @@ static int moxart_remove(struct platform_device *pdev) > if (!IS_ERR_OR_NULL(host->dma_chan_rx)) > dma_release_channel(host->dma_chan_rx); > mmc_remove_host(mmc); > - mmc_free_host(mmc); > > writel(0, host->base + REG_INTERRUPT_MASK); > writel(0, host->base + REG_POWER_CONTROL); > writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF, > host->base + REG_CLOCK_CONTROL); > + mmc_free_host(mmc); > > return 0; > } > -- > 2.35.0 >
diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c index 16d1c7a43d33..b6eb75f4bbfc 100644 --- a/drivers/mmc/host/moxart-mmc.c +++ b/drivers/mmc/host/moxart-mmc.c @@ -705,12 +705,12 @@ static int moxart_remove(struct platform_device *pdev) if (!IS_ERR_OR_NULL(host->dma_chan_rx)) dma_release_channel(host->dma_chan_rx); mmc_remove_host(mmc); - mmc_free_host(mmc); writel(0, host->base + REG_INTERRUPT_MASK); writel(0, host->base + REG_POWER_CONTROL); writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF, host->base + REG_CLOCK_CONTROL); + mmc_free_host(mmc); return 0; }
It was reported that the mmc host structure could be accessed after it was freed in moxart_remove(), so fix this by saving the base register of the device and using it instead of the pointer dereference. Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Xiyu Yang <xiyuyang19@fudan.edu.cn> Cc: Xin Xiong <xiongx18@fudan.edu.cn> Cc: Xin Tan <tanxin.ctf@gmail.com> Cc: Tony Lindgren <tony@atomide.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: linux-mmc@vger.kernel.org Cc: stable <stable@vger.kernel.org> Reported-by: whitehat002 <hackyzh002@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- v2: changed to only move mmc_free_host() call as per Ulf's request drivers/mmc/host/moxart-mmc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)