From: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Subject: fs/binfmt_elf: fix PT_LOAD p_align values for loaders
Rui Salvaterra reported that Aisleroit solitaire crashes with "Wrong
__data_start/_end pair" assertion from libgc after update to v5.17-rc1.
Bisection pointed to commit 9630f0d60fec ("fs/binfmt_elf: use PT_LOAD
p_align values for static PIE") that fixed handling of static PIEs, but
made the condition that guards load_bias calculation to exclude loader
binaries.
Restoring the check for presence of interpreter fixes the problem.
Link: https://lkml.kernel.org/r/20220202121433.3697146-1-rppt@xxxxxxxxxx
Fixes: 9630f0d60fec ("fs/binfmt_elf: use PT_LOAD p_align values for static PIE")
Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Reported-by: Rui Salvaterra <rsalvaterra@xxxxxxxxx>
Tested-by: Rui Salvaterra <rsalvaterra@xxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Eric Biederman <ebiederm@xxxxxxxxxxxx>
Cc: "H.J. Lu" <hjl.tools@xxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/fs/binfmt_elf.c~fs-binfmt_elf-fix-pt_load-p_align-values-for-loaders
+++ a/fs/binfmt_elf.c
@@ -1117,7 +1117,7 @@ out_free_interp:
* without MAP_FIXED nor MAP_FIXED_NOREPLACE).
*/
alignment = maximum_alignment(elf_phdata, elf_ex->e_phnum);
- if (alignment > ELF_MIN_ALIGN) {
+ if (interpreter || alignment > ELF_MIN_ALIGN) {
load_bias = ELF_ET_DYN_BASE;
if (current->flags & PF_RANDOMIZE)
load_bias += arch_mmap_rnd();
_
