Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date: Sat, 22 Mar 2014 08:53:07 -0400
From: "Anthony G. Basile" <basile@...nsource.dyc.edu>
To: musl@...ts.openwall.com
Subject: i686 with -fPIE and -fstack-protector-all

Hi,

I've hit a bug with 1.0.0 on i686.  When building with 
-fstack-protector-all and -fPIE, I get an undefined reference to 
`__stack_chk_fail_local'.  I do not get this on x86_64:

i686:

i686-musl-vanilla ~ # gcc -fstack-protector-all -fPIE -o test test.c
/tmp/ccmdheAK.o: In function `main':
test.c:(.text+0x28): undefined reference to `__stack_chk_fail_local'
/usr/lib/gcc/i686-gentoo-linux-musl/4.7.3/../../../../i686-gentoo-linux-musl/bin/ld: 
test: hidden symbol `__stack_chk_fail_local' isn't defined
/usr/lib/gcc/i686-gentoo-linux-musl/4.7.3/../../../../i686-gentoo-linux-musl/bin/ld: 
final link failed: Bad value
collect2: error: ld returned 1 exit status

i686-musl-vanilla ~ # gcc -fstack-protector-all -o test test.c

i686-musl-vanilla ~ # gcc -fPIE -o test test.c


By contrast for amd64:

amd64-musl-vanilla ~ # echo "int main() { ; return 0 ; }" > test.c
amd64-musl-vanilla ~ # gcc -fstack-protector-all -fPIE -o test test.c
amd64-musl-vanilla ~ # gcc -fstack-protector-all -o test test.c
amd64-musl-vanilla ~ # gcc -fPIE -o test test.c


Doing a compile without link and checking the symbols confirms the problem:

i686-musl-vanilla ~ # gcc -fstack-protector-all -fPIE  -c test.c
i686-musl-vanilla ~ # readelf -sW test.o | grep stack
9: 00000000     0 NOTYPE  GLOBAL HIDDEN   UND __stack_chk_fail_local

amd64-musl-vanilla ~ # gcc -fstack-protector-all -fPIE  -c test.c
amd64-musl-vanilla ~ # readelf -sW test.o | grep stack
10: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT  UND __stack_chk_fail


This is obviously how the compiler spits things out and we have the 
exact same symbols (__stack_chk_fail on amd64 and __stack_chk_fail_local 
on i686) irrespective of the c library.

Where is __stack_chk_fail_local resolved?

-- 
Anthony G. Basile, Ph. D.
Chair of Information Technology
D'Youville College
Buffalo, NY 14201
(716) 829-8197

Powered by blists - more mailing lists

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.