[PATCH 11/18] Annotate conditional output parameters with _Success_

[Césaire Mounah <cesaire.mounah@xxxxxxxxxx>]

Some functions that return a success flag only write their output
parameters on success. Annotate them with _Success_ so that code analysis
does not assume the outputs are valid on failure.

Also fix annotations found on the way: the HW_FIND_ADAPTER Again
parameter is _In_ in storport.h, BufferGet's Pfn is not a pointer, the
xenvbd Base64 __Decode writes up to three bytes, and PdoReadWrite reads
its Srb.

No functional change.

Signed-off-by: Césaire Mounah <cesaire.mounah@xxxxxxxxxx>
---
 src/xencrsh/buffer.c | 3 ++-
 src/xencrsh/buffer.h | 3 ++-
 src/xencrsh/driver.c | 2 +-
 src/xencrsh/pdo.c    | 2 +-
 src/xenvbd/adapter.c | 2 +-
 src/xenvbd/base64.c  | 7 ++++---
 src/xenvbd/ring.c    | 1 +
 7 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/src/xencrsh/buffer.c b/src/xencrsh/buffer.c
index ef897f1..5a0c84d 100644
--- a/src/xencrsh/buffer.c
+++ b/src/xencrsh/buffer.c
@@ -98,10 +98,11 @@ BufferTerminate(
     __Buffer.Next = 0;
 }
 
+_Success_(return)
 BOOLEAN
 BufferGet(
     _Out_ PULONG        BufferId,
-    _Outptr_ PFN_NUMBER *Pfn
+    _Out_ PFN_NUMBER    *Pfn
     )
 {
     ULONG               BufId;
diff --git a/src/xencrsh/buffer.h b/src/xencrsh/buffer.h
index 39df51d..86294ac 100644
--- a/src/xencrsh/buffer.h
+++ b/src/xencrsh/buffer.h
@@ -45,10 +45,11 @@ extern VOID
 BufferTerminate(
     );
 
+_Success_(return)
 extern BOOLEAN
 BufferGet(
     _Out_ PULONG        BufferId,
-    _Outptr_ PFN_NUMBER *Pfn
+    _Out_ PFN_NUMBER    *Pfn
     );
 
 extern VOID
diff --git a/src/xencrsh/driver.c b/src/xencrsh/driver.c
index 70589b1..5874dea 100644
--- a/src/xencrsh/driver.c
+++ b/src/xencrsh/driver.c
@@ -198,7 +198,7 @@ HwFindAdapter(
     _In_ PVOID                              BusInformation,
     _In_ PSTR                               ArgumentString,
     _Inout_ PPORT_CONFIGURATION_INFORMATION ConfigInfo,
-    _Out_ PBOOLEAN                          Again
+    _In_ PBOOLEAN                           Again
     )
 {
     UNREFERENCED_PARAMETER(Context);
diff --git a/src/xencrsh/pdo.c b/src/xencrsh/pdo.c
index d130fc8..b0c77bc 100644
--- a/src/xencrsh/pdo.c
+++ b/src/xencrsh/pdo.c
@@ -768,7 +768,7 @@ __ValidateSectors(
 static BOOLEAN
 PdoReadWrite(
     _Inout_ PXENVBD_PDO         Pdo,
-    _Out_ PSCSI_REQUEST_BLOCK   Srb
+    _Inout_ PSCSI_REQUEST_BLOCK Srb
     )
 {
     NTSTATUS                    Status;
diff --git a/src/xenvbd/adapter.c b/src/xenvbd/adapter.c
index 5dafe07..5809af7 100644
--- a/src/xenvbd/adapter.c
+++ b/src/xenvbd/adapter.c
@@ -2103,7 +2103,7 @@ AdapterHwFindAdapter(
     _In_ PVOID                              BusInformation,
     _In_ PSTR                               ArgumentString,
     _Inout_ PPORT_CONFIGURATION_INFORMATION ConfigInfo,
-    _Out_ PBOOLEAN                          Again
+    _In_ PBOOLEAN                           Again
     )
 {
     UNREFERENCED_PARAMETER(DevExt);
diff --git a/src/xenvbd/base64.c b/src/xenvbd/base64.c
index df398aa..7f20c40 100644
--- a/src/xenvbd/base64.c
+++ b/src/xenvbd/base64.c
@@ -72,11 +72,12 @@ __DecodeChar(
     return 0xFF;
 }
 
+_Success_(return >= 0)
 static DECLSPEC_NOINLINE CHAR
 __Decode(
-    _Out_ PUCHAR    Dst,
-    _In_ PSTR       Src,
-    _In_ ULONG      Left
+    _Out_writes_(3) PUCHAR      Dst,
+    _In_reads_(Left) PSTR       Src,
+    _In_ ULONG                  Left
     )
 {
     UCHAR           Values[4];
diff --git a/src/xenvbd/ring.c b/src/xenvbd/ring.c
index cd5093c..1d8df78 100644
--- a/src/xenvbd/ring.c
+++ b/src/xenvbd/ring.c
@@ -619,6 +619,7 @@ BlkifRingQueueRequests(
     }
 }
 
+_Success_(return)
 static BOOLEAN
 BlkifRingPrepareSegment(
     _In_ PXENVBD_BLKIF_RING BlkifRing,
-- 
2.55.0.windows.5



--
Césaire Mounah | Vates Windows Guest Tools Engineer

XCP-ng & Xen Orchestra - Vates solutions

web: https://vates.tech