From 26a6409156ba8539b2b332f799486572f1f8bab2 Mon Sep 17 00:00:00 2001
From: Isaac Brodsky <isaac@isaacbrodsky.com>
Date: Fri, 16 Jul 2021 16:23:34 -0700
Subject: [PATCH] Backport fix potential segfault in kRing due to invalid digit
 (#498) (#500)

* Backport fix potential segfault in kRing due to invalid digit (#498)

* Backport CI config
---
 .github/workflows/test-linux.yml   |  6 +++---
 .github/workflows/test-macos.yml   |  4 ++--
 .github/workflows/test-website.yml |  6 +++---
 .github/workflows/test-windows.yml |  6 +++---
 CHANGELOG.md                       |  4 ++++
 VERSION                            |  2 +-
 src/apps/testapps/testKRing.c      | 18 ++++++++++++++++++
 src/h3lib/lib/algos.c              |  5 ++++-
 8 files changed, 38 insertions(+), 13 deletions(-)

diff --git a/.github/workflows/test-linux.yml b/.github/workflows/test-linux.yml
index 04244b79e..6d4a8570f 100644
--- a/.github/workflows/test-linux.yml
+++ b/.github/workflows/test-linux.yml
@@ -2,9 +2,9 @@ name: test-linux
 
 on:
   push:
-    branches: [master]
+    branches: [master, stable-*]
   pull_request:
-    branches: [master]
+    branches: [master, stable-*]
 
 jobs:
   tests:
@@ -23,7 +23,7 @@ jobs:
       - name: Install Doxygen
         run: |
           sudo apt update
-          sudo apt-get install doxygen graphviz
+          sudo apt-get install doxygen graphviz clang-format-9
 
       - name: Configure build
         run: cmake -Bbuild -DWARNINGS_AS_ERRORS=ON .
diff --git a/.github/workflows/test-macos.yml b/.github/workflows/test-macos.yml
index 4474fab8c..356e0141e 100644
--- a/.github/workflows/test-macos.yml
+++ b/.github/workflows/test-macos.yml
@@ -2,9 +2,9 @@ name: test-macos
 
 on:
   push:
-    branches: [master]
+    branches: [master, stable-*]
   pull_request:
-    branches: [master]
+    branches: [master, stable-*]
 
 jobs:
   tests:
diff --git a/.github/workflows/test-website.yml b/.github/workflows/test-website.yml
index 2bb16fbec..e36ee4157 100644
--- a/.github/workflows/test-website.yml
+++ b/.github/workflows/test-website.yml
@@ -2,9 +2,9 @@ name: test-website
 
 on:
   push:
-    branches: [master]
+    branches: [master, stable-*]
   pull_request:
-    branches: [master]
+    branches: [master, stable-*]
 
 jobs:
   tests:
@@ -16,7 +16,7 @@ jobs:
 
       - uses: actions/setup-node@v1
         with:
-          node-version: 10.x
+          node-version: 12.x
 
       - name: Install FOSSA
         run: |
diff --git a/.github/workflows/test-windows.yml b/.github/workflows/test-windows.yml
index e7211cc84..0585755dc 100644
--- a/.github/workflows/test-windows.yml
+++ b/.github/workflows/test-windows.yml
@@ -2,9 +2,9 @@ name: test-windows
 
 on:
   push:
-    branches: [master]
+    branches: [master, stable-*]
   pull_request:
-    branches: [master]
+    branches: [master, stable-*]
 
 jobs:
   tests:
@@ -24,7 +24,7 @@ jobs:
 
       - name: Configure build
         shell: cmd
-        run: cmake -Bbuild -A ${{ matrix.arch }} -DWARNINGS_AS_ERRORS=ON .
+        run: cmake -Bbuild -A ${{ matrix.arch }} -DWARNINGS_AS_ERRORS=ON -DBUILD_SHARED_LIBS=OFF -DBUILD_TESTING=ON .
 
       - name: Build
         working-directory: build
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 909178fd4..51d2b3b11 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@ The public API of this library consists of the functions declared in file
 
 ## [Unreleased]
 
+## [3.7.2] - 2021-07-15
+### Fixed
+- `gridDisk` of invalid indexes should not crash. (#498)
+
 ## [3.7.1] - 2020-10-05
 ### Fixed
 - Finding invalid edge boundaries should not crash. (#399)
diff --git a/VERSION b/VERSION
index a76ccff2a..0b2eb36f5 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.7.1
+3.7.2
diff --git a/src/apps/testapps/testKRing.c b/src/apps/testapps/testKRing.c
index 82274b173..084c4fdd0 100644
--- a/src/apps/testapps/testKRing.c
+++ b/src/apps/testapps/testKRing.c
@@ -351,4 +351,22 @@ SUITE(kRing) {
             }
         }
     }
+
+    TEST(kRingInvalid) {
+        int k = 1000;
+        int kSz = H3_EXPORT(maxKringSize)(k);
+        H3Index *neighbors = calloc(kSz, sizeof(H3Index));
+        H3_EXPORT(kRing)(0x7fffffffffffffff, k, neighbors);
+        // Assertion is should not crash - should return an error in the future
+        free(neighbors);
+    }
+
+    TEST(kRingInvalidDigit) {
+        int k = 2;
+        int kSz = H3_EXPORT(maxKringSize)(k);
+        H3Index *neighbors = calloc(kSz, sizeof(H3Index));
+        H3_EXPORT(kRing)(0x4d4b00fe5c5c3030, k, neighbors);
+        // Assertion is should not crash - should return an error in the future
+        free(neighbors);
+    }
 }
diff --git a/src/h3lib/lib/algos.c b/src/h3lib/lib/algos.c
index d3b482194..3af83dc91 100644
--- a/src/h3lib/lib/algos.c
+++ b/src/h3lib/lib/algos.c
@@ -317,7 +317,10 @@ H3Index h3NeighborRotations(H3Index origin, Direction dir, int* rotations) {
         } else {
             Direction oldDigit = H3_GET_INDEX_DIGIT(out, r + 1);
             Direction nextDir;
-            if (isResClassIII(r + 1)) {
+            if (oldDigit == INVALID_DIGIT) {
+                // Only possible on invalid input
+                return H3_NULL;
+            } else if (isResClassIII(r + 1)) {
                 H3_SET_INDEX_DIGIT(out, r + 1, NEW_DIGIT_II[oldDigit][dir]);
                 nextDir = NEW_ADJUSTMENT_II[oldDigit][dir];
             } else {