From 439058ced617fbb3febc017b9e93bb7387f309e0 Mon Sep 17 00:00:00 2001 From: Michael Bommarito Date: Tue, 16 Jun 2026 22:18:59 -0400 Subject: [PATCH] media: v4l2-ctrls: validate AV1 tile counts The stateless AV1 decoders use tile_info.tile_cols and tile_rows as loop bounds and as indices into the mi_*_starts[] and *_in_sbs_minus_1[] arrays, as the divisor for context_update_tile_id, and their product bounds the per-tile descriptor buffers, but std_validate_compound() does not bound these u8 fields. Reject a V4L2_CTRL_TYPE_AV1_FRAME whose tile_cols or tile_rows exceeds V4L2_AV1_MAX_TILE_COLS / _ROWS, or whose product exceeds V4L2_AV1_MAX_TILE_COUNT. A zero tile count is left to the consuming driver so the zero-initialised control that existing userspace submits is still accepted. Fixes: 9de30f579980 ("media: Add AV1 uAPI") Assisted-by: Claude:claude-opus-4-8 Cc: stable@vger.kernel.org Signed-off-by: Michael Bommarito Reviewed-by: Benjamin Gaignard Signed-off-by: Hans Verkuil --- drivers/media/v4l2-core/v4l2-ctrls-core.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-ctrls-core.c b/drivers/media/v4l2-core/v4l2-ctrls-core.c index 9b6121a3a2d2..648b88c868bc 100644 --- a/drivers/media/v4l2-core/v4l2-ctrls-core.c +++ b/drivers/media/v4l2-core/v4l2-ctrls-core.c @@ -793,10 +793,30 @@ static int validate_av1_film_grain(struct v4l2_ctrl_av1_film_grain *fg) return 0; } +static int validate_av1_tile_info(struct v4l2_av1_tile_info *t) +{ + /* + * tile_cols and tile_rows index the per-tile descriptor arrays and + * bound the tile loops in the stateless AV1 drivers; the product + * bounds the total tile descriptor count. + */ + if (t->tile_cols > V4L2_AV1_MAX_TILE_COLS || + t->tile_rows > V4L2_AV1_MAX_TILE_ROWS) + return -EINVAL; + + if ((u32)t->tile_cols * t->tile_rows > V4L2_AV1_MAX_TILE_COUNT) + return -EINVAL; + + return 0; +} + static int validate_av1_frame(struct v4l2_ctrl_av1_frame *f) { int ret = 0; + ret = validate_av1_tile_info(&f->tile_info); + if (ret) + return ret; ret = validate_av1_quantization(&f->quantization); if (ret) return ret;