| Message ID | 3ed8c627e3f1353e5539b458e596c4112121b3ba.1610986541.git.szabolcs.nagy@arm.com |
|---|---|
| State | New |
| Headers | show |
| Series | fix ifunc with static pie [BZ #27072] | expand |
On 18/01/2021 13:24, Szabolcs Nagy via Libc-alpha wrote: > From: "H.J. Lu" <hjl.tools@gmail.com> > > In static PIE, set the default _dl_sysinfo in _dl_aux_init, instead of > using the RELATIVE relocation to intialize it. > > This is needed for fixing bug 27072 on x86. > --- > elf/dl-support.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/elf/dl-support.c b/elf/dl-support.c > index 384080dd80..5acd59290f 100644 > --- a/elf/dl-support.c > +++ b/elf/dl-support.c > @@ -200,7 +200,12 @@ 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; > +uintptr_t _dl_sysinfo > +/* NB: Avoid RELATIVE relocation in static PIE. */ > +# ifndef BUILD_PIE_DEFAULT > + = DL_SYSINFO_DEFAULT > +# endif > +; > #endif > #ifdef NEED_DL_SYSINFO_DSO > /* Address of the ELF headers in the vsyscall page. */ > @@ -238,6 +243,11 @@ _dl_aux_init (ElfW(auxv_t) *av) > uid_t uid = 0; > gid_t gid = 0; > > +#if defined NEED_DL_SYSINFO && BUILD_PIE_DEFAULT > + /* NB: Avoid RELATIVE relocation in static PIE. */ > + GL(dl_sysinfo) = DL_SYSINFO_DEFAULT; > +#endif > + Couldn't we make it the default instead? > _dl_auxv = av; > for (; av->a_type != AT_NULL; ++av) > switch (av->a_type) >
diff --git a/elf/dl-support.c b/elf/dl-support.c index 384080dd80..5acd59290f 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -200,7 +200,12 @@ 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; +uintptr_t _dl_sysinfo +/* NB: Avoid RELATIVE relocation in static PIE. */ +# ifndef BUILD_PIE_DEFAULT + = DL_SYSINFO_DEFAULT +# endif +; #endif #ifdef NEED_DL_SYSINFO_DSO /* Address of the ELF headers in the vsyscall page. */ @@ -238,6 +243,11 @@ _dl_aux_init (ElfW(auxv_t) *av) uid_t uid = 0; gid_t gid = 0; +#if defined NEED_DL_SYSINFO && BUILD_PIE_DEFAULT + /* 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)
From: "H.J. Lu" <hjl.tools@gmail.com> In static PIE, set the default _dl_sysinfo in _dl_aux_init, instead of using the RELATIVE relocation to intialize it. This is needed for fixing bug 27072 on x86. --- elf/dl-support.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)