From: Eliot Courtney <ecourtney@nvidia.com>
Date: Fri, 6 Mar 2026 07:22:01 +0000 (+0900)
Subject: gpu: nova-core: gsp: add checking oversized commands
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=41584c71342e6046fc5af0bd7823e6c0c53ffb0c;p=thirdparty%2Fkernel%2Flinux.git

gpu: nova-core: gsp: add checking oversized commands

The limit is 16 pages for a single command sent to the GSP. Return an
error if `allocate_command` is called with a too large size.

Tested-by: Zhi Wang <zhiw@nvidia.com>
Signed-off-by: Eliot Courtney <ecourtney@nvidia.com>
Link: https://patch.msgid.link/20260306-cmdq-continuation-v6-4-cc7b629200ee@nvidia.com
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
---

diff --git a/drivers/gpu/nova-core/gsp/cmdq.rs b/drivers/gpu/nova-core/gsp/cmdq.rs
index 12849bc057f24..8b970523d789a 100644
--- a/drivers/gpu/nova-core/gsp/cmdq.rs
+++ b/drivers/gpu/nova-core/gsp/cmdq.rs
@@ -32,7 +32,8 @@ use crate::{
             GspMsgElement,
             MsgFunction,
             MsgqRxHeader,
-            MsgqTxHeader, //
+            MsgqTxHeader,
+            GSP_MSG_QUEUE_ELEMENT_SIZE_MAX, //
         },
         PteArray,
         GSP_PAGE_SHIFT,
@@ -300,9 +301,13 @@ impl DmaGspMem {
     ///
     /// # Errors
     ///
+    /// - `EMSGSIZE` if the command is larger than [`GSP_MSG_QUEUE_ELEMENT_SIZE_MAX`].
     /// - `ETIMEDOUT` if space does not become available within the timeout.
     /// - `EIO` if the command header is not properly aligned.
     fn allocate_command(&mut self, size: usize, timeout: Delta) -> Result<GspCommand<'_>> {
+        if size_of::<GspMsgElement>() + size > GSP_MSG_QUEUE_ELEMENT_SIZE_MAX {
+            return Err(EMSGSIZE);
+        }
         read_poll_timeout(
             || Ok(self.driver_write_area_size()),
             |available_bytes| *available_bytes >= size_of::<GspMsgElement>() + size,
diff --git a/drivers/gpu/nova-core/gsp/fw.rs b/drivers/gpu/nova-core/gsp/fw.rs
index 4b998485360b0..6005362450cb1 100644
--- a/drivers/gpu/nova-core/gsp/fw.rs
+++ b/drivers/gpu/nova-core/gsp/fw.rs
@@ -39,6 +39,10 @@ use crate::{
     },
 };
 
+/// Maximum size of a single GSP message queue element in bytes.
+pub(crate) const GSP_MSG_QUEUE_ELEMENT_SIZE_MAX: usize =
+    num::u32_as_usize(bindings::GSP_MSG_QUEUE_ELEMENT_SIZE_MAX);
+
 /// Empty type to group methods related to heap parameters for running the GSP firmware.
 enum GspFwHeapParams {}
 
diff --git a/drivers/gpu/nova-core/gsp/fw/r570_144/bindings.rs b/drivers/gpu/nova-core/gsp/fw/r570_144/bindings.rs
index 6d25fe0bffa97..334e8be5fde8e 100644
--- a/drivers/gpu/nova-core/gsp/fw/r570_144/bindings.rs
+++ b/drivers/gpu/nova-core/gsp/fw/r570_144/bindings.rs
@@ -43,6 +43,7 @@ pub const GSP_FW_HEAP_SIZE_OVERRIDE_LIBOS3_BAREMETAL_MAX_MB: u32 = 280;
 pub const GSP_FW_WPR_META_REVISION: u32 = 1;
 pub const GSP_FW_WPR_META_MAGIC: i64 = -2577556379034558285;
 pub const REGISTRY_TABLE_ENTRY_TYPE_DWORD: u32 = 1;
+pub const GSP_MSG_QUEUE_ELEMENT_SIZE_MAX: u32 = 65536;
 pub type __u8 = ffi::c_uchar;
 pub type __u16 = ffi::c_ushort;
 pub type __u32 = ffi::c_uint;