From 45585c3aa285854face65293acc95eff73063d6d Mon Sep 17 00:00:00 2001 From: Pengpeng Hou Date: Sun, 20 Sep 2026 11:43:29 +0800 Subject: [PATCH] drm/imagination: clamp freelist reconstruction requests The firmware reconstruction count controls accesses to the request's fixed freelist ID array and the copy into the fixed response array. Neither access currently bounds the count to those protocol arrays. Clamp the count to the request capacity, which is shared by the response layout, and use that count consistently for reconstruction and response publication. Keep the firmware recovery exchange instead of dropping an oversized request without a response, as discussed with the firmware maintainer. The issue was found by our static-analysis tool. Fixes: 6eedddab733b ("drm/imagination: Implement free list and HWRT create and destroy ioctls") Assisted-by: gpt 5 Signed-off-by: Pengpeng Hou Reviewed-by: Alessio Belle Link: https://patch.msgid.link/20260920034329.16614-1-hppiscas@163.com Signed-off-by: Brajesh Gupta --- drivers/gpu/drm/imagination/pvr_free_list.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/imagination/pvr_free_list.c b/drivers/gpu/drm/imagination/pvr_free_list.c index e85cac83834c..faf5e586d8dc 100644 --- a/drivers/gpu/drm/imagination/pvr_free_list.c +++ b/drivers/gpu/drm/imagination/pvr_free_list.c @@ -8,6 +8,7 @@ #include "pvr_vm.h" #include +#include #include #include #include @@ -612,13 +613,21 @@ pvr_free_list_process_reconstruct_req(struct pvr_device *pvr_dev, }; struct rogue_fwif_freelists_reconstruction_data *resp = &resp_cmd.cmd_data.free_lists_reconstruction_data; + u32 count = min_t(u32, req->freelist_count, + ARRAY_SIZE(req->freelist_ids)); - for (u32 i = 0; i < req->freelist_count; i++) + if (count != req->freelist_count) { + drm_warn_once(from_pvr_device(pvr_dev), + "Requested reconstruction of %u freelists, limiting to %u\n", + req->freelist_count, count); + } + + for (u32 i = 0; i < count; i++) pvr_free_list_reconstruct(pvr_dev, req->freelist_ids[i]); - resp->freelist_count = req->freelist_count; + resp->freelist_count = count; memcpy(resp->freelist_ids, req->freelist_ids, - req->freelist_count * sizeof(resp->freelist_ids[0])); + count * sizeof(resp->freelist_ids[0])); WARN_ON(pvr_kccb_send_cmd(pvr_dev, &resp_cmd, NULL)); }