Mesa (18.3): glsl: free or reuse memory allocated for TF varying

[GitLab Mirror]

Module: Mesa
Branch: 18.3
Commit: 6b9b7ce38ca3ae7745ed6faf95f4a7b03843ebb4
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=6b9b7ce38ca3ae7745ed6faf95f4a7b03843ebb4

Author: Gert Wollny <gert.wollny at collabora.com>
Date:   Fri Nov 16 19:12:46 2018 +0100

glsl: free or reuse memory allocated for TF varying

When a shader program is de-serialized the gl_shader_program passed in
may actually still hold memory allocations for the transform feedback
varyings. If that is the case, free the varying names and reallocate
the new storage for the names array.

This fixes a memory leak:
Direct leak of 48 byte(s) in 6 object(s) allocated from:
 in malloc (/usr/lib64/gcc/x86_64-pc-linux-gnu/7.3.0/libasan.so+0xdb880)
 in transform_feedback_varyings ../../samba/mesa/src/mesa/main/transformfeedback.c:875
 in _mesa_TransformFeedbackVaryings ../../samba/mesa/src/mesa/main/transformfeedback.c:985
 ...
Indirect leak of 42 byte(s) in 6 object(s) allocated from:
  in __interceptor_strdup (/usr/lib64/gcc/x86_64-pc-linux-gnu/7.3.0/libasan.so+0x761c8)
  in transform_feedback_varyings ../../samba/mesa/src/mesa/main/transformfeedback.c:887
  in _mesa_TransformFeedbackVaryings ../../samba/mesa/src/mesa/main/transformfeedback.c:985

Fixes: ab2643e4b06f63c93a57624003679903442634a8
   glsl: serialize data from glTransformFeedbackVaryings

Signed-off-by: Gert Wollny <gert.wollny at collabora.com>
Reviewed-by: Tapani Pälli <tapani.palli at intel.com>
(cherry picked from commit f5d053702fa976a3112d9c6a2425430365db40f8)

---

 src/compiler/glsl/serialize.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/compiler/glsl/serialize.cpp b/src/compiler/glsl/serialize.cpp
index 267700e7e7..26d8ec4b75 100644
--- a/src/compiler/glsl/serialize.cpp
+++ b/src/compiler/glsl/serialize.cpp
@@ -360,13 +360,20 @@ read_xfb(struct blob_reader *metadata, struct gl_shader_program *shProg)
    if (xfb_stage == ~0u)
       return;
 
+   if (shProg->TransformFeedback.VaryingNames)  {
+      for (unsigned i = 0; i < shProg->TransformFeedback.NumVarying; ++i)
+         free(shProg->TransformFeedback.VaryingNames[i]);
+   }
+
    /* Data set by glTransformFeedbackVaryings. */
    shProg->TransformFeedback.BufferMode = blob_read_uint32(metadata);
    blob_copy_bytes(metadata, &shProg->TransformFeedback.BufferStride,
                    sizeof(shProg->TransformFeedback.BufferStride));
    shProg->TransformFeedback.NumVarying = blob_read_uint32(metadata);
+
    shProg->TransformFeedback.VaryingNames = (char **)
-      malloc(shProg->TransformFeedback.NumVarying * sizeof(GLchar *));
+      realloc(shProg->TransformFeedback.VaryingNames,
+             shProg->TransformFeedback.NumVarying * sizeof(GLchar *));
    /* Note, malloc used with VaryingNames. */
    for (unsigned i = 0; i < shProg->TransformFeedback.NumVarying; i++)
       shProg->TransformFeedback.VaryingNames[i] =