From: deraadt <deraadt@openbsd.org>
Date: Tue, 8 Nov 2022 06:55:53 +0000 (+0000)
Subject: Since the introduction of automatic immutable from the kernel, the munmap()
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=59d66fc38050f5ef8d28636c01023b38b7dcfe9f;p=openbsd

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 riscv64, tested by jca
---

diff --git a/libexec/ld.so/riscv64/ld.script b/libexec/ld.so/riscv64/ld.script
index d0231259a0b..77f3a846a29 100644
--- a/libexec/ld.so/riscv64/ld.script
+++ b/libexec/ld.so/riscv64/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;
@@ -25,10 +26,12 @@ 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);