[PATCH AUTOSEL 6.1 30/33] drm/amd: Fix an out of bounds error in BIOS parser

Sasha Levin
2023-05-01T03:14:14Z

From: Mario Limonciello <mario.limonciello@amd.com>

[ Upstream commit d116db180decec1b21bba31d2ff495ac4d8e1b83 ]

The array is hardcoded to 8 in atomfirmware.h, but firmware provides
a bigger one sometimes. Deferencing the larger array causes an out
of bounds error.

commit 4fc1ba4aa589 ("drm/amd/display: fix array index out of bound error
in bios parser") fixed some of this, but there are two other cases
not covered by it. Fix those as well.

Reported-by: erhard_f@mailbox.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214853
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2473
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c b/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c
index 074e70a5c458e..e507d2e1410b7 100644
--- a/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c
+++ b/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c
@@ -516,11 +516,8 @@ static enum bp_result get_gpio_i2c_info(
info->i2c_slave_address = record->i2c_slave_addr;

/* TODO: check how to get register offset for en, Y, etc. */
- info->gpio_info.clk_a_register_index =
- le16_to_cpu(
- header->gpio_pin[table_index].data_a_reg_index);
- info->gpio_info.clk_a_shift =
- header->gpio_pin[table_index].gpio_bitshift;
+ info->gpio_info.clk_a_register_index = le16_to_cpu(pin->data_a_reg_index);
+ info->gpio_info.clk_a_shift = pin->gpio_bitshift;

return BP_RESULT_OK;
}
--
2.39.2