[PATCH 0/1] MR4944: dlls/msvcrt: Free previous environment variable when clearing

[David Kahurani (＠kahurani)]

Shifting the rest of the variables by one towards indices of lesser value
overwrites the variable being cleared and effectively leaks it.

Signed-off-by: David Kahurani <k.kahurani(a)gmail.com>

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/4944

[PATCH 1/1] dlls/msvcrt: Free previous environment variable when clearing

[David Kahurani]

From: David Kahurani <k.kahurani(a)gmail.com>

Shifting the rest of the variables by one towards indices of lesser value
overwrites the variable being cleared and effectively leaks it.

Signed-off-by: David Kahurani <k.kahurani(a)gmail.com>
---
 dlls/msvcrt/environ.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/dlls/msvcrt/environ.c b/dlls/msvcrt/environ.c
index aa857afa615..09d2842366f 100644
--- a/dlls/msvcrt/environ.c
+++ b/dlls/msvcrt/environ.c
@@ -161,8 +161,15 @@ static int env_set(char **env, wchar_t **wenv)
     *eq = '=';
     if (!eq[1])
     {
+        int start = idx;
+        
         for(; MSVCRT__environ[idx]; idx++)
-            MSVCRT__environ[idx] = MSVCRT__environ[idx + 1];
+        {
+           if (idx == start)
+               free(MSVCRT__environ[start]);
+            
+           MSVCRT__environ[idx] = MSVCRT__environ[idx + 1];
+        }
     }
     else if (MSVCRT__environ[idx])
     {
@@ -187,8 +194,15 @@ static int env_set(char **env, wchar_t **wenv)
     *weq = '=';
     if (!weq[1])
     {
+        int start = idx;
+        
         for(; MSVCRT__wenviron[idx]; idx++)
-            MSVCRT__wenviron[idx] = MSVCRT__wenviron[idx + 1];
+        {
+           if (idx == start)
+               free(MSVCRT__wenviron[start]);
+            
+           MSVCRT__wenviron[idx] = MSVCRT__wenviron[idx + 1];
+        }
     }
     else if (MSVCRT__wenviron[idx])
     {
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/4944

[eric pouech (＠epo)]

please move the free() calls before & outside the for loop

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/4944#note_59147