On Tuesday, May 7, 2019 1:46:15 AM CEST Srinivas Pandruvada wrote:
> On Thu, 2019-05-02 at 16:00 -0400, Lenny Szubowicz wrote:
> > Correct the LPIT end address which is passed into lpit_process()
> > and the end address limit test in lpit_process().
> >
> > The LPI state descriptor subtables follow the fixed sized
> > acpi_lpit_header up to the end of the LPIT. The last LPI state
> > descriptor can end at exactly the end of the LPIT.
> >
> > Note that this is a fix to a latent problem. Although incorrect,
> > the unpatched version works because the passed in end address
> > is just slightly beyond the actual end of the LPIT and the size
> > of the ACPI LPIT header is smaller than the size of the only
> > currently defined LPI state descriptor, acpi_lpit_native.
> >
> > Signed-off-by: Lenny Szubowicz <lszubowi@xxxxxxxxxx>
> Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
>
> > ---
> > drivers/acpi/acpi_lpit.c | 7 +++----
> > 1 file changed, 3 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/acpi/acpi_lpit.c b/drivers/acpi/acpi_lpit.c
> > index e43cb71b6972..8b170a07908a 100644
> > --- a/drivers/acpi/acpi_lpit.c
> > +++ b/drivers/acpi/acpi_lpit.c
> > @@ -137,7 +137,7 @@ static void lpit_update_residency(struct
> > lpit_residency_info *info,
> >
> > static void lpit_process(u64 begin, u64 end)
> > {
> > - while (begin + sizeof(struct acpi_lpit_native) < end) {
> > + while (begin + sizeof(struct acpi_lpit_native) <= end) {
> > struct acpi_lpit_native *lpit_native = (struct
> > acpi_lpit_native *)begin;
> >
> > if (!lpit_native->header.type && !lpit_native-
> > >header.flags) {
> > @@ -156,7 +156,6 @@ static void lpit_process(u64 begin, u64 end)
> > void acpi_init_lpit(void)
> > {
> > acpi_status status;
> > - u64 lpit_begin;
> > struct acpi_table_lpit *lpit;
> >
> > status = acpi_get_table(ACPI_SIG_LPIT, 0, (struct
> > acpi_table_header **)&lpit);
> > @@ -164,6 +163,6 @@ void acpi_init_lpit(void)
> > if (ACPI_FAILURE(status))
> > return;
> >
> > - lpit_begin = (u64)lpit + sizeof(*lpit);
> > - lpit_process(lpit_begin, lpit_begin + lpit->header.length);
> > + lpit_process((u64)lpit + sizeof(*lpit),
> > + (u64)lpit + lpit->header.length);
> > }
>
>
Patch applied, thanks!
