[PATCH 1/2] habanalabs: block scalar load_and_exe on external queue

[Oded Gabbay]

In Gaudi, the user can't execute scalar load_and_exe on external queue
because it can be a security hole. The driver doesn't parse the commands
being loaded and it can be msg_prot, which the user isn't allowed to use.

Signed-off-by: Oded Gabbay <oded.gab...@gmail.com>
---
 drivers/misc/habanalabs/gaudi/gaudi.c         | 25 ++++++++++++++++++-
 .../habanalabs/include/gaudi/gaudi_packets.h  |  3 +++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/habanalabs/gaudi/gaudi.c 
b/drivers/misc/habanalabs/gaudi/gaudi.c
index 61f88e9884ce..f34ac8d35a14 100644
--- a/drivers/misc/habanalabs/gaudi/gaudi.c
+++ b/drivers/misc/habanalabs/gaudi/gaudi.c
@@ -3790,6 +3790,25 @@ static int gaudi_validate_dma_pkt_no_mmu(struct 
hl_device *hdev,
                                                src_in_host);
 }
 
+static int gaudi_validate_load_and_exe_pkt(struct hl_device *hdev,
+                                       struct hl_cs_parser *parser,
+                                       struct packet_load_and_exe *user_pkt)
+{
+       u32 cfg;
+
+       cfg = le32_to_cpu(user_pkt->cfg);
+
+       if (cfg & GAUDI_PKT_LOAD_AND_EXE_CFG_DST_MASK) {
+               dev_err(hdev->dev,
+                       "User not allowed to use Load and Execute\n");
+               return -EPERM;
+       }
+
+       parser->patched_cb_size += sizeof(struct packet_load_and_exe);
+
+       return 0;
+}
+
 static int gaudi_validate_cb(struct hl_device *hdev,
                        struct hl_cs_parser *parser, bool is_mmu)
 {
@@ -3838,6 +3857,11 @@ static int gaudi_validate_cb(struct hl_device *hdev,
                        rc = -EPERM;
                        break;
 
+               case PACKET_LOAD_AND_EXE:
+                       rc = gaudi_validate_load_and_exe_pkt(hdev, parser,
+                               (struct packet_load_and_exe *) user_pkt);
+                       break;
+
                case PACKET_LIN_DMA:
                        parser->contains_dma_pkt = true;
                        if (is_mmu)
@@ -3855,7 +3879,6 @@ static int gaudi_validate_cb(struct hl_device *hdev,
                case PACKET_FENCE:
                case PACKET_NOP:
                case PACKET_ARB_POINT:
-               case PACKET_LOAD_AND_EXE:
                        parser->patched_cb_size += pkt_size;
                        break;
 
diff --git a/drivers/misc/habanalabs/include/gaudi/gaudi_packets.h 
b/drivers/misc/habanalabs/include/gaudi/gaudi_packets.h
index 9a5800b0086b..0f0cd067bb43 100644
--- a/drivers/misc/habanalabs/include/gaudi/gaudi_packets.h
+++ b/drivers/misc/habanalabs/include/gaudi/gaudi_packets.h
@@ -197,6 +197,9 @@ struct packet_wait {
        __le32 ctl;
 };
 
+#define GAUDI_PKT_LOAD_AND_EXE_CFG_DST_SHIFT   0
+#define GAUDI_PKT_LOAD_AND_EXE_CFG_DST_MASK    0x00000001
+
 struct packet_load_and_exe {
        __le32 cfg;
        __le32 ctl;
-- 
2.17.1