lkml.org 
[lkml]   [2019]   [Feb]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2 1/2] pci: imx6: avoid dereferencing program counter from user mode
From
Date
Am Dienstag, den 04.12.2018, 14:27 +0100 schrieb Stefan Agner:
> The custom fault handler is currently only meant to handle kernel
> mode bus faults. Exit in case the abort happened in user mode.
>
> Signed-off-by: Stefan Agner <stefan@agner.ch>

Reviewed-by: Lucas Stach <l.stach@pengutronix.de>

> ---
>  drivers/pci/controller/dwc/pci-imx6.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 69f86234f7c0..54a29e441303 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -270,8 +270,14 @@ static int imx6q_pcie_abort_handler(unsigned long addr,
>   unsigned int fsr, struct pt_regs *regs)
>  {
>   unsigned long pc = instruction_pointer(regs);
> - unsigned long instr = *(unsigned long *)pc;
> - int reg = (instr >> 12) & 15;
> + unsigned long instr;
> + int reg;
> +
> + if (user_mode(regs))
> + return 1;
> +
> + instr = *(unsigned long *)pc;
> + reg = (instr >> 12) & 15;
>  
>   /*
>    * If the instruction being executed was a read,

\
 
 \ /
  Last update: 2019-02-11 17:57    [W:0.039 / U:3.800 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site