Use the illumos libc SSP implementation for -fstack-protector (9.3.0)

[citrus-it]

With this patch applied, and with the compiler configured to output 64-bit objects by default:

% gcc -dumpspecs | grep -A3 link_ssp *link_ssp: %{fstack-protector|fstack-protector-all|fstack-protector-strong|fstack-protector-explicit:%{m32:%{fpie|fPIE|fpic|fPIC:-lssp_ns}}} 

When configured to output 32-bit objects by default, this looks as follows:
(This is from gcc7 built with the same patch - gcc7 on OmniOS produces 32-bit by default)

*link_ssp: %{fstack-protector|fstack-protector-all|fstack-protector-strong|fstack-protector-explicit:%{!m64:%{fpie|fPIE|fpic|fPIC:-lssp_ns}}} 

Testing so far has been with this small program:

#include <stdio.h> #include <string.h> const char* buffer_long = "This is a long long string"; void stack_overflows_here(void) { char buffer_short[20]; strcpy(buffer_short, buffer_long); printf("Overflow triggered.\n"); } int main(void) { printf("Starting "); #ifdef _LP64 printf("64-bit "); #else printf("32-bit "); #endif #ifdef __pic__ printf("- PIC: %d ", __pic__); #endif #ifdef __pie__ printf("- PIE: %d ", __pie__); #endif printf("\n"); stack_overflows_here(); return 0; }

and the following test driver script

#!/bin/ksh o="-fstack-protector" function check { typeset f="$1" echo "*** $f" nm $f | grep __stack_chk | cut -d'|' -f3- [[ $f = *.o ]] && return (./$f) && banner "$f DID NOT CRASH" } for b in 32 64; do for f in "" pic PIC pie PIE; do echo "******" echo "****** $b $f" echo "******" [ -n "$f" ] && fopt="-f$f" || fopt= op=overflow-$b-$f gcc -m$b $o $fopt -o $op overflow.c check $op op=overflow-$b-$f.o gcc -m$b $o $fopt -o $op -c overflow.c check $op op=overflow-$b-$f-2stage gcc -m$b $o $fopt -o $op overflow-$b-$f.o check overflow-$b-$f-2stage op=overflow-$b-$f-2stage-nosplink gcc -m$b $fopt -o $op overflow-$b-$f.o # Expect link failure for 32-bit pic/pie case if [ $b != 32 -o -z "$f" ]; then check $op else # Test again and link with ssp_ns gcc -m$b $fopt -o $op overflow-$b-$f.o -lssp_ns check $op fi op=overflow-$b-$f-2stage-ld ld -$b -o overflow-$b-$f-2stage-ld overflow-$b-$f.o -lc # Expect link failure for 32-bit pic/pie case if [ $b != 32 -o -z "$f" ]; then check $op else # Test again and link the correct object ld -$b -o overflow-$b-$f-2stage-ld overflow-$b-$f.o \ -lc -l ssp_ns check $op fi echo done echo done

which is producing the expected output. Showing that the __stack_chk_fail_local symbol only comes into play for 32-bit PIC objects, and that gcc does the right thing when linking those objects.

****** ****** 32 ****** *** overflow-32- 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 4|OBJT |GLOB |0 |24 |__stack_chk_guard ./test[23]: check: line 10: 3885: Abort(coredump) *** overflow-32-.o 0|NOTY |GLOB |0 |UNDEF |__stack_chk_fail 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-32--2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 4|OBJT |GLOB |0 |24 |__stack_chk_guard ./test[31]: check: line 10: 3897: Abort(coredump) *** overflow-32--2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 4|OBJT |GLOB |0 |24 |__stack_chk_guard ./test[37]: check: line 10: 3904: Abort(coredump) *** overflow-32--2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 4|OBJT |GLOB |0 |17 |__stack_chk_guard ./test[48]: check: line 10: 3909: Abort(coredump) ****** ****** 32 pic ****** *** overflow-32-pic 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[23]: check: line 10: 3918: Abort(coredump) *** overflow-32-pic.o 0|NOTY |GLOB |2 |UNDEF |__stack_chk_fail_local 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-32-pic-2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[31]: check: line 10: 3930: Abort(coredump) Undefined first referenced symbol in file __stack_chk_fail_local overflow-32-pic.o (symbol scope specifies local binding) ld: fatal: symbol referencing errors. No output written to overflow-32-pic-2stage-nosplink collect2: error: ld returned 1 exit status *** overflow-32-pic-2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[41]: check: line 10: 3940: Abort(coredump) Undefined first referenced symbol in file __stack_chk_fail_local overflow-32-pic.o (symbol scope specifies local binding) ld: fatal: symbol referencing errors. No output written to overflow-32-pic-2stage-ld *** overflow-32-pic-2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |12 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[53]: check: line 10: 3946: Abort(coredump) ****** ****** 32 PIC ****** *** overflow-32-PIC 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[23]: check: line 10: 3955: Abort(coredump) *** overflow-32-PIC.o 0|NOTY |GLOB |2 |UNDEF |__stack_chk_fail_local 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-32-PIC-2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[31]: check: line 10: 3967: Abort(coredump) Undefined first referenced symbol in file __stack_chk_fail_local overflow-32-PIC.o (symbol scope specifies local binding) ld: fatal: symbol referencing errors. No output written to overflow-32-PIC-2stage-nosplink collect2: error: ld returned 1 exit status *** overflow-32-PIC-2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[41]: check: line 10: 3977: Abort(coredump) Undefined first referenced symbol in file __stack_chk_fail_local overflow-32-PIC.o (symbol scope specifies local binding) ld: fatal: symbol referencing errors. No output written to overflow-32-PIC-2stage-ld *** overflow-32-PIC-2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |12 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[53]: check: line 10: 3983: Abort(coredump) ****** ****** 32 pie ****** *** overflow-32-pie 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[23]: check: line 10: 3992: Abort(coredump) *** overflow-32-pie.o 0|NOTY |GLOB |2 |UNDEF |__stack_chk_fail_local 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-32-pie-2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[31]: check: line 10: 4004: Abort(coredump) Undefined first referenced symbol in file __stack_chk_fail_local overflow-32-pie.o (symbol scope specifies local binding) ld: fatal: symbol referencing errors. No output written to overflow-32-pie-2stage-nosplink collect2: error: ld returned 1 exit status *** overflow-32-pie-2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[41]: check: line 10: 4014: Abort(coredump) Undefined first referenced symbol in file __stack_chk_fail_local overflow-32-pie.o (symbol scope specifies local binding) ld: fatal: symbol referencing errors. No output written to overflow-32-pie-2stage-ld *** overflow-32-pie-2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |12 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[53]: check: line 10: 4020: Abort(coredump) ****** ****** 32 PIE ****** *** overflow-32-PIE 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[23]: check: line 10: 4029: Abort(coredump) *** overflow-32-PIE.o 0|NOTY |GLOB |2 |UNDEF |__stack_chk_fail_local 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-32-PIE-2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[31]: check: line 10: 4041: Abort(coredump) Undefined first referenced symbol in file __stack_chk_fail_local overflow-32-PIE.o (symbol scope specifies local binding) ld: fatal: symbol referencing errors. No output written to overflow-32-PIE-2stage-nosplink collect2: error: ld returned 1 exit status *** overflow-32-PIE-2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |13 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[41]: check: line 10: 4051: Abort(coredump) Undefined first referenced symbol in file __stack_chk_fail_local overflow-32-PIE.o (symbol scope specifies local binding) ld: fatal: symbol referencing errors. No output written to overflow-32-PIE-2stage-ld *** overflow-32-PIE-2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 29|FUNC |LOCL |2 |12 |__stack_chk_fail_local 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[53]: check: line 10: 4057: Abort(coredump) ****** ****** 64 ****** *** overflow-64- 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 8|OBJT |GLOB |0 |24 |__stack_chk_guard ./test[23]: check: line 10: 4066: Abort(coredump) *** overflow-64-.o 0|NOTY |GLOB |0 |UNDEF |__stack_chk_fail 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-64--2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 8|OBJT |GLOB |0 |24 |__stack_chk_guard ./test[31]: check: line 10: 4078: Abort(coredump) *** overflow-64--2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 8|OBJT |GLOB |0 |24 |__stack_chk_guard ./test[37]: check: line 10: 4085: Abort(coredump) *** overflow-64--2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 8|OBJT |GLOB |0 |19 |__stack_chk_guard ./test[48]: check: line 10: 4090: Abort(coredump) ****** ****** 64 pic ****** *** overflow-64-pic 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[23]: check: line 10: 4099: Abort(coredump) *** overflow-64-pic.o 0|NOTY |GLOB |0 |UNDEF |__stack_chk_fail 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-64-pic-2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[31]: check: line 10: 4111: Abort(coredump) *** overflow-64-pic-2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[37]: check: line 10: 4118: Abort(coredump) *** overflow-64-pic-2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[48]: check: line 10: 4123: Abort(coredump) ****** ****** 64 PIC ****** *** overflow-64-PIC 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[23]: check: line 10: 4132: Abort(coredump) *** overflow-64-PIC.o 0|NOTY |GLOB |0 |UNDEF |__stack_chk_fail 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-64-PIC-2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[31]: check: line 10: 4144: Abort(coredump) *** overflow-64-PIC-2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[37]: check: line 10: 4151: Abort(coredump) *** overflow-64-PIC-2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[48]: check: line 10: 4156: Abort(coredump) ****** ****** 64 pie ****** *** overflow-64-pie 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[23]: check: line 10: 4165: Abort(coredump) *** overflow-64-pie.o 0|NOTY |GLOB |0 |UNDEF |__stack_chk_fail 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-64-pie-2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[31]: check: line 10: 4177: Abort(coredump) *** overflow-64-pie-2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[37]: check: line 10: 4184: Abort(coredump) *** overflow-64-pie-2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[48]: check: line 10: 4189: Abort(coredump) ****** ****** 64 PIE ****** *** overflow-64-PIE 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[23]: check: line 10: 4198: Abort(coredump) *** overflow-64-PIE.o 0|NOTY |GLOB |0 |UNDEF |__stack_chk_fail 0|NOTY |GLOB |0 |UNDEF |__stack_chk_guard *** overflow-64-PIE-2stage 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[31]: check: line 10: 4210: Abort(coredump) *** overflow-64-PIE-2stage-nosplink 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[37]: check: line 10: 4217: Abort(coredump) *** overflow-64-PIE-2stage-ld 0|FUNC |GLOB |0 |UNDEF |__stack_chk_fail 0|OBJT |GLOB |0 |UNDEF |__stack_chk_guard ./test[48]: check: line 10: 4222: Abort(coredump) 

[rmustacc]

Do we have test suite results for this?