diff options
author | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2020-06-09 16:12:01 -0300 |
---|---|---|
committer | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2020-06-09 16:12:01 -0300 |
commit | 364e569945c044fd18c70ee1bc851364534aef97 (patch) | |
tree | ad461207558d0452455a8180cf5d8b1e6e37d0be | |
parent | 63295f1f7fa052fabcb4d69d49203cf33a7deef0 (diff) | |
download | lua-github-364e569945c044fd18c70ee1bc851364534aef97.tar.gz |
Avoid calling 'fprintf' with NULL
Avoid undefined behavior in calls like «fprintf("%s", NULL)».
('lua_writestringerror' is implemented as 'fprintf', and 'lua_tostring'
can return NULL if object is not a string.)
-rw-r--r-- | lauxlib.c | 4 | ||||
-rw-r--r-- | ldblib.c | 2 | ||||
-rw-r--r-- | ltests.c | 4 |
3 files changed, 7 insertions, 3 deletions
@@ -995,8 +995,10 @@ static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) { static int panic (lua_State *L) { + const char *msg = lua_tostring(L, -1); + if (msg == NULL) msg = "error object is not a string"; lua_writestringerror("PANIC: unprotected error in call to Lua API (%s)\n", - lua_tostring(L, -1)); + msg); return 0; /* return to Lua to abort */ } @@ -417,7 +417,7 @@ static int db_debug (lua_State *L) { return 0; if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") || lua_pcall(L, 0, 0, 0)) - lua_writestringerror("%s\n", lua_tostring(L, -1)); + lua_writestringerror("%s\n", luaL_tolstring(L, -1, NULL)); lua_settop(L, 0); /* remove eventual returns */ } } @@ -73,8 +73,10 @@ static void badexit (const char *fmt, const char *s1, const char *s2) { static int tpanic (lua_State *L) { + const char *msg = lua_tostring(L, -1); + if (msg == NULL) msg = "error object is not a string"; return (badexit("PANIC: unprotected error in call to Lua API (%s)\n", - lua_tostring(L, -1), NULL), + msg, NULL), 0); /* do not return to Lua */ } |