Re: [PATCH v2 2/7] kallsyms: Fix address-checks for kernel related range

From: Steven Rostedt
Date: Wed Jul 28 2021 - 10:46:55 EST


On Wed, 28 Jul 2021 16:13:15 +0800
Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:

> The is_kernel_inittext/is_kernel_text/is_kernel function should not
> include the end address(the labels _einittext, _etext and _end) when
> check the address range, the issue exists since Linux v2.6.12.
>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Cc: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx>
> Cc: Petr Mladek <pmladek@xxxxxxxx>
> Acked-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
> Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>

Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

-- Steve

> ---
> include/linux/kallsyms.h | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
> index 2a241e3f063f..b016c62f30a6 100644
> --- a/include/linux/kallsyms.h
> +++ b/include/linux/kallsyms.h
> @@ -27,21 +27,21 @@ struct module;
> static inline int is_kernel_inittext(unsigned long addr)
> {
> if (addr >= (unsigned long)_sinittext
> - && addr <= (unsigned long)_einittext)
> + && addr < (unsigned long)_einittext)
> return 1;
> return 0;
> }
>
> static inline int is_kernel_text(unsigned long addr)
> {
> - if ((addr >= (unsigned long)_stext && addr <= (unsigned long)_etext))
> + if ((addr >= (unsigned long)_stext && addr < (unsigned long)_etext))
> return 1;
> return in_gate_area_no_mm(addr);
> }
>
> static inline int is_kernel(unsigned long addr)
> {
> - if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
> + if (addr >= (unsigned long)_stext && addr < (unsigned long)_end)
> return 1;
> return in_gate_area_no_mm(addr);
> }