> -----Original Message----- > From: Devel [mailto:devel-bounces@xxxxxxxxxx] On Behalf Of Moore, Robert > Sent: Wednesday, September 6, 2017 9:43 AM > To: Zhenhua <lizhenhuajiyang@xxxxxxx>; devel@xxxxxxxxxx; Zheng, Lv > <lv.zheng@xxxxxxxxx>; Wysocki, Rafael J <rafael.j.wysocki@xxxxxxxxx>; > lenb@xxxxxxxxxx; linux-acpi@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx > Subject: Re: [Devel] [PATCH 1/1] ACPI: NULL pointer checking > > > > > -----Original Message----- > > From: Zhenhua [mailto:lizhenhuajiyang@xxxxxxx] > > Sent: Wednesday, September 6, 2017 6:35 AM > > To: devel@xxxxxxxxxx; Moore, Robert <robert.moore@xxxxxxxxx>; Zheng, > > Lv <lv.zheng@xxxxxxxxx>; Wysocki, Rafael J > > <rafael.j.wysocki@xxxxxxxxx>; lenb@xxxxxxxxxx; > > linux-acpi@xxxxxxxxxxxxxxx; linux- kernel@xxxxxxxxxxxxxxx > > Cc: Zhenhua <lizhenhuajiyang@xxxxxxx> > > Subject: [PATCH 1/1] ACPI: NULL pointer checking > > > > These two pointers should be checked, for some broken devices they may > > cause system crash. > > > > Signed-off-by: Zhenhua <lizhenhuajiyang@xxxxxxx> > > --- > > drivers/acpi/acpica/nsaccess.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/acpi/acpica/nsaccess.c > > b/drivers/acpi/acpica/nsaccess.c index f2733f51ca8d..151abb0ef4d5 > > 100644 > > --- a/drivers/acpi/acpica/nsaccess.c > > +++ b/drivers/acpi/acpica/nsaccess.c > > @@ -338,7 +338,7 @@ acpi_ns_lookup(union acpi_generic_state > *scope_info, > > return_ACPI_STATUS(AE_AML_INTERNAL); > > } > > > > - if (!(flags & ACPI_NS_PREFIX_IS_SCOPE)) { > > + if ((!prefix_node) && (!(flags & ACPI_NS_PREFIX_IS_SCOPE))) { > [Moore, Robert] > > Is there an actual case where the original code failed? > > [Moore, Robert] Prefix_node is guaranteed to be valid at this point in the code. > > > /* > > * This node might not be a actual "scope" node (such as > a > > * Device/Method, etc.) It could be a Package or other > object @@ > > -369,7 +369,7 @@ acpi_ns_lookup(union acpi_generic_state *scope_info, > > ACPI_DEBUG_PRINT((ACPI_DB_NAMES, > > "Null Pathname (Zero segments), Flags=%X\n", > > flags)); > > - } else { > > + } else if (path) { [Moore, Robert] Likewise, "path" is guaranteed to be valid at this point. > > /* > > * Name pointer is valid (and must be in internal name > > format) > > * > > -- > > 2.14.1 > > > > _______________________________________________ > Devel mailing list > Devel@xxxxxxxxxx > https://lists.acpica.org/mailman/listinfo/devel -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
