CVSROOT: /cvs Module name: src Changes by: k...@cvs.openbsd.org 2021/05/25 11:01:36
Modified files: libexec/ld.so : loader.c Log message: program headers: do not rely on DYNAMIC coming before GNU_RELRO Except for some specific cases (thanks guenther) ELF mandates nothing but the file header be at a fixed location, hence ld.so(1) must not assume any specific order for headers, segments, etc. Looping over the program header table to parse segment headers, _dl_boot() creates the executable object upon DYNAMIC and expects it to be set upon GNU_RELRO, resulting in a NULL dereference iff that order is reversed. Store relocation bits in temporary variables and update the executable object once all segment headers are parsed to lift this dependency. Under __mips__ _dl_boot() later on uses the same temporary variable, so move nothing but the declaration out of MI code so as to not alter the MD code's logic/behaviour. Found while porting patchelf(1) from NixOS. OK guenther