| Message ID | 20170827203205.7rymov2jglbcibbz@var.youpi.perso.aquilenet.fr |
|---|---|
| State | New |
| Headers | show |
| Series | [hurd,commited] : Fix static initialization with -fstack-protector-strong | expand |
On 27 Aug 2017, Samuel Thibault outgrape: > When linked statically, TLS initialization is not achieved before > mach_init and alike, so ssp accesses to tcbhead's stack_guard would > crash. We can just avoid using ssp in the few functions needed before > TLS is set up. Oh blast I forgot all about Hurd didn't I. Sorry. > diff --git a/hurd/Makefile b/hurd/Makefile > index 9205822b24..b44b9b80c6 100644 > --- a/hurd/Makefile > +++ b/hurd/Makefile > @@ -81,6 +81,10 @@ $(inlines:%=$(objpfx)%.c): $(objpfx)%-inlines.c: %.h > echo '#include "$<"') > $@-new > mv -f $@-new $@ > generated += $(inlines:=.c) > + > +# Avoid ssp before TLS is initialized. > +CFLAGS-hurdstartup.o = $(no-stack-protector) > +CFLAGS-RPC_exec_startup_get_info.o = $(no-stack-protector) This certainly looks like the right sort of thing to be doing, though I don't have anything I can test it on right now. -fstack-protector-all might well comb out some more cases.
Nick Alcock, on ven. 15 sept. 2017 17:38:38 +0100, wrote: > On 27 Aug 2017, Samuel Thibault outgrape: > > When linked statically, TLS initialization is not achieved before > > mach_init and alike, so ssp accesses to tcbhead's stack_guard would > > crash. We can just avoid using ssp in the few functions needed before > > TLS is set up. > > Oh blast I forgot all about Hurd didn't I. > > Sorry. No problem. Determining which functions need it is not trivial anyway :) Samuel
diff --git a/hurd/Makefile b/hurd/Makefile index 9205822b24..b44b9b80c6 100644 --- a/hurd/Makefile +++ b/hurd/Makefile @@ -81,6 +81,10 @@ $(inlines:%=$(objpfx)%.c): $(objpfx)%-inlines.c: %.h echo '#include "$<"') > $@-new mv -f $@-new $@ generated += $(inlines:=.c) + +# Avoid ssp before TLS is initialized. +CFLAGS-hurdstartup.o = $(no-stack-protector) +CFLAGS-RPC_exec_startup_get_info.o = $(no-stack-protector) include ../mach/Machrules include ../Rules diff --git a/mach/Makefile b/mach/Makefile index 127cad00ca..b4f18b1525 100644 --- a/mach/Makefile +++ b/mach/Makefile @@ -53,6 +53,15 @@ server-interfaces := mach/exc # Clear any environment value. generated = + +# Avoid ssp before TLS is initialized. +CFLAGS-mach_init.o = $(no-stack-protector) +CFLAGS-RPC_vm_statistics.o = $(no-stack-protector) +CFLAGS-RPC_vm_map.o = $(no-stack-protector) +CFLAGS-RPC_vm_protect.o = $(no-stack-protector) +CFLAGS-RPC_i386_set_gdt.o = $(no-stack-protector) +CFLAGS-RPC_i386_set_ldt.o = $(no-stack-protector) +CFLAGS-RPC_task_get_special_port.o = $(no-stack-protector) # Translate GNU names for CPUs into the names used in Mach header files. mach-machine = $(patsubst powerpc,ppc,$(base-machine))
When linked statically, TLS initialization is not achieved before mach_init and alike, so ssp accesses to tcbhead's stack_guard would crash. We can just avoid using ssp in the few functions needed before TLS is set up. * mach/Makefile (CFLAGS-mach_init.o, CFLAGS-RPC_vm_statistics.o, CFLAGS-RPC_vm_map.o, CFLAGS-RPC_vm_protect.o, CFLAGS-RPC_i386_set_gdt.o, CFLAGS-RPC_i386_set_ldt.o, CFLAGS-RPC_task_get_special_port.o): Add $(no-stack-protector). * hurd/Makefile (CFLAGS-hurdstartup.o, CFLAGS-RPC_exec_startup_get_info.o): Add $(no-stack-protector).