diff options
| author | Leonid Lisovskiy <lly.dev@gmail.com> | 2016-06-20 20:29:45 +0300 |
|---|---|---|
| committer | Waldemar Brodkorb <wbx@uclibc-ng.org> | 2016-06-22 08:02:51 +0200 |
| commit | bc5949fd4f8cddf4eee74492c86a8a72f4dee0e7 (patch) | |
| tree | 68cf04f3eade770ecd41bfb782bc5e9f51acbe94 /ldso | |
| parent | 0bc1394750885d4e4b2064aff6c48dd542c6f4b8 (diff) | |
ldso: fix dlsym hang when reloading DSOs
It can happen under certain cases that the DSO had refcount 0,
but was already loaded. (NODELETE flag is set, or it is pulled
in via both NEEDED dependency and explicit dlopen()).
Add extra reference count for NODELETE objects, this will
ensure that the reference count never drops below one.
It is improved version of
http://lists.busybox.net/pipermail/uclibc/2013-June/047826.html
Signed-off-by: Leonid Lisovskiy <lly.dev@gmail.com>
Diffstat (limited to 'ldso')
| -rw-r--r-- | ldso/ldso/dl-elf.c | 2 | ||||
| -rw-r--r-- | ldso/libdl/libdl.c | 4 |
2 files changed, 4 insertions, 2 deletions
diff --git a/ldso/ldso/dl-elf.c b/ldso/ldso/dl-elf.c index 8f71aeb05..a046aeb74 100644 --- a/ldso/ldso/dl-elf.c +++ b/ldso/ldso/dl-elf.c @@ -884,6 +884,8 @@ struct elf_resolve *_dl_load_elf_shared_library(unsigned int rflags, #endif (*rpnt)->dyn = tpnt; tpnt->usage_count++; + if (tpnt->rtld_flags & RTLD_NODELETE) + tpnt->usage_count++; #ifdef __LDSO_STANDALONE_SUPPORT__ tpnt->libtype = (epnt->e_type == ET_DYN) ? elf_lib : elf_executable; #else diff --git a/ldso/libdl/libdl.c b/ldso/libdl/libdl.c index 489c78759..0cf3b7037 100644 --- a/ldso/libdl/libdl.c +++ b/ldso/libdl/libdl.c @@ -818,7 +818,7 @@ static int do_dlclose(void *vhandle, int need_fini) _dl_handles = rpnt->next_handle; _dl_if_debug_print("%s: usage count: %d\n", handle->dyn->libname, handle->dyn->usage_count); - if (handle->dyn->usage_count != 1 || (handle->dyn->rtld_flags & RTLD_NODELETE)) { + if (handle->dyn->usage_count != 1) { handle->dyn->usage_count--; free(handle); return 0; @@ -840,7 +840,7 @@ static int do_dlclose(void *vhandle, int need_fini) for (j = 0; j < handle->init_fini.nlist; ++j) { tpnt = handle->init_fini.init_fini[j]; tpnt->usage_count--; - if (tpnt->usage_count == 0 && !(tpnt->rtld_flags & RTLD_NODELETE)) { + if (tpnt->usage_count == 0) { if ((tpnt->dynamic_info[DT_FINI] || tpnt->dynamic_info[DT_FINI_ARRAY]) && need_fini |