From 7f8a129b37ce0887218b6edf0b506f944e2d77b9 Mon Sep 17 00:00:00 2001 From: deraadt Date: Wed, 9 Nov 2022 18:39:35 +0000 Subject: [PATCH] Since the introduction of automatic immutable from the kernel, the munmap() of ld.so boot.text region is now (silently) failing because the region is contained within the text LOAD, which is immutable. So create a new btext LOAD with flags PF_X|PF_R|PF_OPENBSD_MUTABLE, and place all boot.text objects in there. This LOAD must also be page-aligned so it doesn't skip unmapping some of the object region, previously it was hilariously unaligned. ok kettenis and guenther seemed to like it also This one is for 32-bit arm, tested by phessler --- libexec/ld.so/arm/ld.script | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/libexec/ld.so/arm/ld.script b/libexec/ld.so/arm/ld.script index f18abe07795..ae7cc098ef0 100644 --- a/libexec/ld.so/arm/ld.script +++ b/libexec/ld.so/arm/ld.script @@ -2,6 +2,7 @@ PHDRS { rodata PT_LOAD FILEHDR PHDRS FLAGS (4); text PT_LOAD; + btext PT_LOAD FLAGS (0x08000005); data PT_LOAD; random PT_OPENBSD_RANDOMIZE; relro PT_GNU_RELRO; @@ -26,10 +27,12 @@ SECTIONS . = ALIGN(0x1000); .boot.text : { + . = ALIGN(0x1000); boot_text_start = .; *(.boot.text) + . = ALIGN(0x1000); boot_text_end = .; - } :text + } :btext /* RELRO DATA */ . = DATA_SEGMENT_ALIGN (0x10000, 0x1000); -- 2.20.1