diff options
| author | Luca Coelho <luciano.coelho@intel.com> | 2025-05-20 11:26:58 +0300 |
|---|---|---|
| committer | Mika Kahola <mika.kahola@intel.com> | 2025-06-05 15:37:50 +0300 |
| commit | c206a27eb72f13d345d51818152e8707d4563b51 (patch) | |
| tree | 22209dd4d417dbdaa1de2eb67b79dfdd0c382f56 | |
| parent | e117100acb6d2dd90da01a88616a3b9261b0e99a (diff) | |
drm/i915/dkl: return if tc_port is invalid in dkl_phy_set_hip_idx()
In dkl_phy_set_hip_idx(), we may try to shift a value negatively,
whose behavior is undefined. This can happen because we define
TC_PORT_NONE to -1, so theoretically tc_port could be -1. We will
then use tc_port to shift to the correct address of the specified
port, but if it's negative, anything can happen.
If this happens or tc_port exceeds I915_MAX_TC_PORTS, it's safer to
return with a warning than risk an invalid write.
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Link: https://lore.kernel.org/r/20250520082917.1302665-2-luciano.coelho@intel.com
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dkl_phy.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_dkl_phy.c b/drivers/gpu/drm/i915/display/intel_dkl_phy.c index dad7192132ad..35e919eae369 100644 --- a/drivers/gpu/drm/i915/display/intel_dkl_phy.c +++ b/drivers/gpu/drm/i915/display/intel_dkl_phy.c @@ -25,7 +25,9 @@ dkl_phy_set_hip_idx(struct intel_display *display, struct intel_dkl_phy_reg reg) { enum tc_port tc_port = DKL_REG_TC_PORT(reg); - drm_WARN_ON(display->drm, tc_port < TC_PORT_1 || tc_port >= I915_MAX_TC_PORTS); + if (drm_WARN_ON(display->drm, + tc_port < TC_PORT_1 || tc_port >= I915_MAX_TC_PORTS)) + return; intel_de_write(display, HIP_INDEX_REG(tc_port), |