linux-user/elfload: Unprotect regions before core dump

By unprotecting regions, we re-instate writability and
unify regions that have been split, which may reduce
the total number of regions.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2024-02-27 08:25:22 -10:00
parent 50e33f52fb
commit 41689bb30c
1 changed files with 22 additions and 0 deletions

View File

@ -3963,6 +3963,8 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
}
#ifdef USE_ELF_CORE_DUMP
#include "exec/translate-all.h"
/*
* Definitions to generate Intel SVR4-like core files.
* These mostly have the same names as the SVR4 types with "target_elf_"
@ -4280,6 +4282,23 @@ static int dump_write(int fd, const void *ptr, size_t size)
return (0);
}
static int wmr_page_unprotect_regions(void *opaque, target_ulong start,
target_ulong end, unsigned long flags)
{
if ((flags & (PAGE_WRITE | PAGE_WRITE_ORG)) == PAGE_WRITE_ORG) {
size_t step = MAX(TARGET_PAGE_SIZE, qemu_host_page_size);
while (1) {
page_unprotect(start, 0);
if (end - start <= step) {
break;
}
start += step;
}
}
return 0;
}
typedef struct {
unsigned count;
size_t size;
@ -4401,6 +4420,9 @@ static int elf_core_dump(int signr, const CPUArchState *env)
cpu_list_lock();
mmap_lock();
/* By unprotecting, we merge vmas that might be split. */
walk_memory_regions(NULL, wmr_page_unprotect_regions);
/*
* Walk through target process memory mappings and
* set up structure containing this information.