linux/arch/um/sys-i386/elfcore.c
Daisuke HATAYAMA 8d9032bbe4 elf coredump: add extended numbering support
The current ELF dumper implementation can produce broken corefiles if
program headers exceed 65535.  This number is determined by the number of
vmas which the process have.  In particular, some extreme programs may use
more than 65535 vmas.  (If you google max_map_count, you can find some
users facing this problem.) This kind of program never be able to generate
correct coredumps.

This patch implements ``extended numbering'' that uses sh_info field of
the first section header instead of e_phnum field in order to represent
upto 4294967295 vmas.

This is supported by
AMD64-ABI(http://www.x86-64.org/documentation.html) and
Solaris(http://docs.sun.com/app/docs/doc/817-1984/).
Of course, we are preparing patches for gdb and binutils.

Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:46 -08:00

84 lines
1.9 KiB
C

#include <linux/elf.h>
#include <linux/coredump.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <asm/elf.h>
Elf32_Half elf_core_extra_phdrs(void)
{
return vsyscall_ehdr ? (((struct elfhdr *)vsyscall_ehdr)->e_phnum) : 0;
}
int elf_core_write_extra_phdrs(struct file *file, loff_t offset, size_t *size,
unsigned long limit)
{
if ( vsyscall_ehdr ) {
const struct elfhdr *const ehdrp =
(struct elfhdr *) vsyscall_ehdr;
const struct elf_phdr *const phdrp =
(const struct elf_phdr *) (vsyscall_ehdr + ehdrp->e_phoff);
int i;
Elf32_Off ofs = 0;
for (i = 0; i < ehdrp->e_phnum; ++i) {
struct elf_phdr phdr = phdrp[i];
if (phdr.p_type == PT_LOAD) {
ofs = phdr.p_offset = offset;
offset += phdr.p_filesz;
} else {
phdr.p_offset += ofs;
}
phdr.p_paddr = 0; /* match other core phdrs */
*size += sizeof(phdr);
if (*size > limit
|| !dump_write(file, &phdr, sizeof(phdr)))
return 0;
}
}
return 1;
}
int elf_core_write_extra_data(struct file *file, size_t *size,
unsigned long limit)
{
if ( vsyscall_ehdr ) {
const struct elfhdr *const ehdrp =
(struct elfhdr *) vsyscall_ehdr;
const struct elf_phdr *const phdrp =
(const struct elf_phdr *) (vsyscall_ehdr + ehdrp->e_phoff);
int i;
for (i = 0; i < ehdrp->e_phnum; ++i) {
if (phdrp[i].p_type == PT_LOAD) {
void *addr = (void *) phdrp[i].p_vaddr;
size_t filesz = phdrp[i].p_filesz;
*size += filesz;
if (*size > limit
|| !dump_write(file, addr, filesz))
return 0;
}
}
}
return 1;
}
size_t elf_core_extra_data_size(void)
{
if ( vsyscall_ehdr ) {
const struct elfhdr *const ehdrp =
(struct elfhdr *)vsyscall_ehdr;
const struct elf_phdr *const phdrp =
(const struct elf_phdr *) (vsyscall_ehdr + ehdrp->e_phoff);
int i;
for (i = 0; i < ehdrp->e_phnum; ++i)
if (phdrp[i].p_type == PT_LOAD)
return (size_t) phdrp[i].p_filesz;
}
return 0;
}