From 893d4fb45bb0811bcc939054e60e37a47a1786c5 Mon Sep 17 00:00:00 2001 From: Ronald Wahl Date: Mon, 4 Feb 2013 14:51:46 +0100 Subject: [PATCH] libc: atexit: reuse free slots at the end of exit functions table Continuosly dlopen and dlclose of shared object will cause a memory leak in atexit function. This fix reuse free slots at the end of the list. For further detail see https://bugs.busybox.net/show_bug.cgi?id=2455 Signed-off-by: Ronald Wahl Tested-by: Filippo Arcidiacono Signed-off-by: Carmelo Amoroso (cherry picked from commit 389cd96704f21549cafc0b5bdcd0ef762b98bc08) --- libc/stdlib/_atexit.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/libc/stdlib/_atexit.c b/libc/stdlib/_atexit.c index 48b97ff..0af8c57 100644 --- a/libc/stdlib/_atexit.c +++ b/libc/stdlib/_atexit.c @@ -240,6 +240,16 @@ struct exit_function attribute_hidden *__new_exitfn(void) __UCLIBC_MUTEX_LOCK(__atexit_lock); + /* + * Reuse free slots at the end of the list. + * This avoids eating memory when dlopen and dlclose modules multiple times. + */ + while (__exit_count > 0) { + if (__exit_function_table[__exit_count-1].type == ef_free) { + --__exit_count; + } else break; + } + #ifdef __UCLIBC_DYNAMIC_ATEXIT__ /* If we are out of function table slots, make some more */ if (__exit_slots < __exit_count+1) { -- 1.7.10.4