diff options
| author | Harry Wentland <harry.wentland@amd.com> | 2026-05-04 16:14:11 -0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2026-05-19 12:13:29 -0400 |
| commit | 86d2b20644b11d21fe52c596e6e922b4590a3e3f (patch) | |
| tree | ac11988d5e14cce6951ad26060d1433b5613cd51 | |
| parent | cd86529ec61474a38c3837fb7823790a7c3f8cce (diff) | |
drm/amd/display: Validate GPIO pin LUT table size before iterating
[Why&How]
The GPIO pin table parsers in get_gpio_i2c_info() and
bios_parser_get_gpio_pin_info() derive an element count from the VBIOS
table_header.structuresize field, then iterate over gpio_pin[] entries.
However, GET_IMAGE() only validates that the table header itself fits
within the BIOS image. If the VBIOS reports a structuresize larger than
the actual mapped data, the loop reads past the end of the BIOS image,
causing an out-of-bounds read.
Fix this by calling bios_get_image() to validate that the full claimed
structuresize is accessible within the BIOS image before entering the
loop in both functions.
Assisted-by: GitHub Copilot:claude-opus-4-6
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Ivan Lipski <ivan.lipski@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit ba5e95b43b773ae1bf1f66ee6b31eb774e65afe3)
Cc: stable@vger.kernel.org
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c | 9 |
1 files changed, 9 insertions, 0 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 a1c08e1cc411..c51c4b2c6fae 100644 --- a/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c +++ b/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c @@ -493,6 +493,10 @@ static enum bp_result get_gpio_i2c_info( - sizeof(struct atom_common_table_header)) / sizeof(struct atom_gpio_pin_assignment); + if (!bios_get_image(&bp->base, DATA_TABLES(gpio_pin_lut), + le16_to_cpu(header->table_header.structuresize))) + return BP_RESULT_BADBIOSTABLE; + pin = (struct atom_gpio_pin_assignment *) header->gpio_pin; for (table_index = 0; table_index < count; table_index++) { @@ -681,6 +685,11 @@ static enum bp_result bios_parser_get_gpio_pin_info( count = (le16_to_cpu(header->table_header.structuresize) - sizeof(struct atom_common_table_header)) / sizeof(struct atom_gpio_pin_assignment); + + if (!bios_get_image(&bp->base, DATA_TABLES(gpio_pin_lut), + le16_to_cpu(header->table_header.structuresize))) + return BP_RESULT_BADBIOSTABLE; + for (i = 0; i < count; ++i) { if (header->gpio_pin[i].gpio_id != gpio_id) continue; |