Commit 1fae1191 authored by Qiuhao Li's avatar Qiuhao Li Committed by Frediano Ziglio
Browse files

reds: fix nullptr deref in red-parse-qxl.cpp

At red-parse-qxl.cpp#L535

        if (qxl_flags & QXL_BITMAP_DIRECT) {
            red-> = red_get_image_data_flat(slots, group_id,

Since qxl-> may from the guest, an attacker can make the
memslot_get_virt() check in red_get_image_data_flat() fail and
return a nullptr.

Then at red-parse-qxl.cpp#L550

        if (qxl_flags & QXL_BITMAP_UNSTABLE) {
            red->>flags |= SPICE_CHUNKS_FLAGS_UNSTABLE;

qxl_flags is assigned as qxl->bitmap.flags before, which can also be
controlled by the attacker, resulting in a NULL pointer dereference.

This dereference seems to be introduced by commit 5ac88aa7


Signed-off-by: Qiuhao Li's avatarQiuhao Li <>
parent 848c231d
Pipeline #307019 passed with stage
in 18 minutes and 12 seconds
......@@ -535,6 +535,9 @@ static SpiceImage *red_get_image(RedMemSlotInfo *slots, int group_id,
red-> = red_get_image_data_flat(slots, group_id,
if (red-> == nullptr) {
goto error;
} else {
size = red_get_data_chunks(slots, group_id,
&chunks, qxl->;
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment