binutils/tests/Regression/RELRO-protection-effective/PURPOSE
2021-04-28 08:26:46 +02:00

35 lines
2.3 KiB
Plaintext

PURPOSE of /tools/binutils/Regression/RELRO-protection-effective
Description: bz1174826
Author: Martin Cermak <mcermak@redhat.com>
Bug summary: RELRO is not read-only on PowerLE
Bugzilla link: https://bugzilla.redhat.com/show_bug.cgi?id=1174826
/*
* Test to exercise PIE and RELRO provided by Roland McGrath <roland@redhat.com>.
*
* Description:
* Simple test for RELRO, which happens to be a PIE too, but that's only
* because this kind of example has to be in PIC code to make RELRO relevant,
* and PIE makes it simpler to write a standalone one-file test than writing
* a DSO.
*
* The "const" makes "foo" .rodata material, and the init to an external symbol
* reference makes it require a data relocation. Enabling -z relro for this
* link puts that .rodata into a RELRO area. This program will crash because
* the page containing "foo" has been made read-only when "main" runs.
* Without RELRO, it would let you modify "foo" even though it's supposed to
* be const.
*
* Test with RELRO should fail:
* $ gcc -pie -fPIE -g -Wl,-z,relro -o relro relro.c
* $ ./relro
* Segmentation fault (core dumped)
*
* Test without RELRO should pass:
* $ gcc -pie -fPIE -g -Wl,-z,norelro -o no-relro relro.c
* $ ./no-relro
*
**/