From 74e1bbfb842a00f9b99e65ca7ca6a3a82ac875f8 Mon Sep 17 00:00:00 2001 From: Mika Kuoppala Date: Mon, 17 Aug 2020 22:59:26 +0300 Subject: [PATCH] drm/i915: Fix cmd parser desc matching with masks commit e5f10d6385cda083037915c12b130887c8831d2b upstream. Our variety of defined gpu commands have the actual command id field and possibly length and flags applied. We did start to apply the mask during initialization of the cmd descriptors but forgot to also apply it on comparisons. Fix comparisons in order to properly deny access with associated commands. v2: fix lri with correct mask (Chris) References: 926abff21a8f ("drm/i915/cmdparser: Ignore Length operands during command matching") Reported-by: Nicolai Stange Cc: stable@vger.kernel.org # v5.4+ Cc: Miroslav Benes Cc: Takashi Iwai Cc: Tyler Hicks Cc: Jon Bloomfield Cc: Chris Wilson Signed-off-by: Mika Kuoppala Reviewed-by: Chris Wilson Link: https://patchwork.freedesktop.org/patch/msgid/20200817195926.12671-1-mika.kuoppala@linux.intel.com (cherry picked from commit 3b4efa148da36f158cce3f662e831af2834b8e0f) Signed-off-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/i915_cmd_parser.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_cmd_parser.c b/drivers/gpu/drm/i915/i915_cmd_parser.c index 372354d33f552..5ac4a999f05a6 100644 --- a/drivers/gpu/drm/i915/i915_cmd_parser.c +++ b/drivers/gpu/drm/i915/i915_cmd_parser.c @@ -1204,6 +1204,12 @@ static u32 *copy_batch(struct drm_i915_gem_object *dst_obj, return dst; } +static inline bool cmd_desc_is(const struct drm_i915_cmd_descriptor * const desc, + const u32 cmd) +{ + return desc->cmd.value == (cmd & desc->cmd.mask); +} + static bool check_cmd(const struct intel_engine_cs *engine, const struct drm_i915_cmd_descriptor *desc, const u32 *cmd, u32 length) @@ -1242,19 +1248,19 @@ static bool check_cmd(const struct intel_engine_cs *engine, * allowed mask/value pair given in the whitelist entry. */ if (reg->mask) { - if (desc->cmd.value == MI_LOAD_REGISTER_MEM) { + if (cmd_desc_is(desc, MI_LOAD_REGISTER_MEM)) { DRM_DEBUG("CMD: Rejected LRM to masked register 0x%08X\n", reg_addr); return false; } - if (desc->cmd.value == MI_LOAD_REGISTER_REG) { + if (cmd_desc_is(desc, MI_LOAD_REGISTER_REG)) { DRM_DEBUG("CMD: Rejected LRR to masked register 0x%08X\n", reg_addr); return false; } - if (desc->cmd.value == MI_LOAD_REGISTER_IMM(1) && + if (cmd_desc_is(desc, MI_LOAD_REGISTER_IMM(1)) && (offset + 2 > length || (cmd[offset + 1] & reg->mask) != reg->value)) { DRM_DEBUG("CMD: Rejected LRI to masked register 0x%08X\n", @@ -1478,7 +1484,7 @@ int intel_engine_cmd_parser(struct intel_engine_cs *engine, break; } - if (desc->cmd.value == MI_BATCH_BUFFER_START) { + if (cmd_desc_is(desc, MI_BATCH_BUFFER_START)) { ret = check_bbstart(cmd, offset, length, batch_length, batch_addr, shadow_addr, jump_whitelist);