From: Ulf Magnusson Date: Sun, 8 Oct 2017 17:11:19 +0000 (+0200) Subject: kconfig: Don't leak 'source' filenames during parsing X-Git-Url: https://jxself.org/git/?p=carl9170fw.git;a=commitdiff_plain;h=42bc2cb9fd5367ea805f291c72c81e67fbcabde5 kconfig: Don't leak 'source' filenames during parsing The 'source_stmt' nonterminal takes a 'prompt', which consists of either a T_WORD or a T_WORD_QUOTE, both of which are always allocated on the heap in zconf.l and need to have their associated strings freed. Free them. The existing code already makes sure to always copy the string, but add a warning to sym_expand_string_value() to make it clear that the string must be copied, just in case. Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix: LEAK SUMMARY: definitely lost: 387,504 bytes in 15,545 blocks ... Summary after the fix: LEAK SUMMARY: definitely lost: 344,616 bytes in 14,355 blocks ... Signed-off-by: Ulf Magnusson Signed-off-by: Masahiro Yamada Signed-off-by: Christian Lamparter --- diff --git a/config/symbol.c b/config/symbol.c index 35e0937..55c95e0 100644 --- a/config/symbol.c +++ b/config/symbol.c @@ -907,6 +907,10 @@ const char *sym_expand_string_value(const char *in) char *res; size_t reslen; + /* + * Note: 'in' might come from a token that's about to be + * freed, so make sure to always allocate a new string + */ reslen = strlen(in) + 1; res = xmalloc(reslen); res[0] = '\0'; diff --git a/config/zconf.y b/config/zconf.y index 27b9b3f..7ca7954 100644 --- a/config/zconf.y +++ b/config/zconf.y @@ -393,6 +393,7 @@ source_stmt: T_SOURCE prompt T_EOL { printd(DEBUG_PARSE, "%s:%d:source %s\n", zconf_curname(), zconf_lineno(), $2); zconf_nextfile($2); + free($2); }; /* comment entry */