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SubjectRe: [patch 1/3] x86/ldt: Free the right LDT memory in write_ldt() error path

* Thomas Gleixner <tglx@linutronix.de> wrote:

> The error path in write_ldt() frees the already installed LDT memory
> instead of the newly allocated which cannot be installed.

s/newly allocated
/newly allocated one

>
> Fixes: f55f0501cbf6 ("x86/pti: Put the LDT in its own PGD if PTI is on")
> Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> ---
> arch/x86/kernel/ldt.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> --- a/arch/x86/kernel/ldt.c
> +++ b/arch/x86/kernel/ldt.c
> @@ -421,7 +421,7 @@ static int write_ldt(void __user *ptr, u
> */
> error = map_ldt_struct(mm, new_ldt, old_ldt ? !old_ldt->slot : 0);
> if (error) {
> - free_ldt_struct(old_ldt);
> + free_ldt_struct(new_ldt);
> goto out_unlock;
> }
>

This bug kind of scares me ...

Reviewed-by: Ingo Molnar <mingo@kernel.org>

Thanks,

Ingo

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