From af3c44826b8ff07082eb5020213652e6b1fadfa4 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Mon, 18 Jan 2021 11:45:46 +0000 Subject: [PATCH] elf: Avoid RELATIVE relocation for _dl_sysinfo Set the default _dl_sysinfo in _dl_aux_init to avoid RELATIVE relocation in static PIE. This is needed for fixing bug 27072 on x86. --- elf/dl-support.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/elf/dl-support.c b/elf/dl-support.c index 384080dd80..7abb65d8e3 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -199,8 +199,9 @@ int _dl_thread_gscope_count; struct dl_scope_free_list *_dl_scope_free_list; #ifdef NEED_DL_SYSINFO -/* Needed for improved syscall handling on at least x86/Linux. */ -uintptr_t _dl_sysinfo = DL_SYSINFO_DEFAULT; +/* Needed for improved syscall handling on at least x86/Linux. NB: Don't + initialize it here to avoid RELATIVE relocation in static PIE. */ +uintptr_t _dl_sysinfo; #endif #ifdef NEED_DL_SYSINFO_DSO /* Address of the ELF headers in the vsyscall page. */ @@ -238,6 +239,11 @@ _dl_aux_init (ElfW(auxv_t) *av) uid_t uid = 0; gid_t gid = 0; +#ifdef NEED_DL_SYSINFO + /* NB: Avoid RELATIVE relocation in static PIE. */ + GL(dl_sysinfo) = DL_SYSINFO_DEFAULT; +#endif + _dl_auxv = av; for (; av->a_type != AT_NULL; ++av) switch (av->a_type) -- 2.29.2