Fix __minimal_malloc segfaults in __mmap due to stack-protector

Starting with commit b05fae4d8e34604a72ee36d2d3164391b76fcf0b
"elf: Use the minimal malloc on tunables_strdup",
I get lots of segfaults in static tests on s390x when also using, e.g.:
export GLIBC_TUNABLES="glibc.elision.enable=1"

tunables_strdup callls __minimal_malloc which tries to call __mmap
due to insufficient space left. __mmap itself first setups a new
stack frame and segfaults when copying the stack-protector canary
from thread-pointer. The latter one is not yet setup.

Thus this patch also turns off stack-protection for mmap.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

diff --git a/misc/Makefile b/misc/Makefile
index 3b66cb9..db40312 100644 (file)
--- a/misc/Makefile
+++ b/misc/Makefile
@@ -149,6 +149,10 @@ CFLAGS-sbrk.o = $(no-stack-protector)
 CFLAGS-sbrk.op = $(no-stack-protector)
 CFLAGS-brk.o = $(no-stack-protector)
 CFLAGS-brk.op = $(no-stack-protector)
+CFLAGS-mmap.o = $(no-stack-protector)
+CFLAGS-mmap.op = $(no-stack-protector)
+CFLAGS-mmap64.o = $(no-stack-protector)
+CFLAGS-mmap64.op = $(no-stack-protector)
 
 include ../Rules