Fix T73537: Particle system Crash

Added sanity check in the flow / obstacle object loops that check if the modifier data is valid. Ideally this should not be needed. However, in remove_particle_systems_from_object() the fluid modifier can get freed. It is not yet clear whether the modifier free call is really needed or not.

1 files changed, 22 insertions, 2 deletions

diff --git a/source/blender/blenkernel/intern/fluid.c b/source/blender/blenkernel/intern/fluid.c
index f19137bf796..91adbf2301d 100644
--- a/source/blender/blenkernel/intern/fluid.c
+++ b/source/blender/blenkernel/intern/fluid.c
@@ -872,6 +872,11 @@ static void update_obstacleflags(FluidDomainSettings *mds,
     FluidModifierData *mmd2 = (FluidModifierData *)modifiers_findByType(coll_ob,
                                                                         eModifierType_Fluid);
 
+    /* Sanity check. */
+    if (!mmd2) {
+      continue;
+    }
+
     if ((mmd2->type & MOD_FLUID_TYPE_EFFEC) && mmd2->effector) {
       FluidEffectorSettings *mes = mmd2->effector;
       if (!mes) {
@@ -959,6 +964,11 @@ static void update_obstacles(Depsgraph *depsgraph,
     FluidModifierData *mmd2 = (FluidModifierData *)modifiers_findByType(coll_ob,
                                                                         eModifierType_Fluid);
 
+    /* Sanity check. */
+    if (!mmd2) {
+      continue;
+    }
+
     /* TODO (sebbas): check if modifier is active? */
     if ((mmd2->type & MOD_FLUID_TYPE_EFFEC) && mmd2->effector) {
       FluidEffectorSettings *mes = mmd2->effector;
@@ -2298,7 +2308,7 @@ static void update_flowsflags(FluidDomainSettings *mds, Object **flowobjs, int n
     FluidModifierData *mmd2 = (FluidModifierData *)modifiers_findByType(coll_ob,
                                                                         eModifierType_Fluid);
 
-    // Sanity check
+    /* Sanity check. */
     if (!mmd2) {
       continue;
     }
@@ -2411,6 +2421,11 @@ static void update_flowsfluids(struct Depsgraph *depsgraph,
     FluidModifierData *mmd2 = (FluidModifierData *)modifiers_findByType(flowobj,
                                                                         eModifierType_Fluid);
 
+    /* Sanity check. */
+    if (!mmd2) {
+      continue;
+    }
+
     /* Check for initialized smoke object. */
     if ((mmd2->type & MOD_FLUID_TYPE_FLOW) && mmd2->flow) {
       FluidFlowSettings *mfs = mmd2->flow;
@@ -2607,6 +2622,11 @@ static void update_flowsfluids(struct Depsgraph *depsgraph,
     FluidModifierData *mmd2 = (FluidModifierData *)modifiers_findByType(flowobj,
                                                                         eModifierType_Fluid);
 
+    /* Sanity check. */
+    if (!mmd2) {
+      continue;
+    }
+
     /* Check for initialized flow object. */
     if ((mmd2->type & MOD_FLUID_TYPE_FLOW) && mmd2->flow) {
       FluidFlowSettings *mfs = mmd2->flow;
@@ -3313,7 +3333,7 @@ static void BKE_fluid_modifier_processDomain(FluidModifierData *mmd,
   guide_parent = mds->guide_parent;
   if (guide_parent) {
     mmd_parent = (FluidModifierData *)modifiers_findByType(guide_parent, eModifierType_Fluid);
-    if (mmd_parent->domain) {
+    if (mmd_parent && mmd_parent->domain) {
       copy_v3_v3_int(mds->guide_res, mmd_parent->domain->res);
     }
   }