s390/kdump: Make elfcorehdr size calculation ABI compliant

There are two ways to pass the vmcoreinfo to the crash kernel 1) via the
os_info mechanism and 2) via the lowcore->vmcore_info field. In the Linux
kernel only the second way is used. However, the first way is ABI for
stand-alone kdump. So other OSes use it to pass additional debug info. Make
the elfcorehdr size calculation aware of both possible ways.

Fixes: 8cce437fbb ("s390/kdump: Fix elfcorehdr size calculation")
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
This commit is contained in:
Philipp Rudo 2018-08-06 13:39:52 +02:00 committed by Heiko Carstens
parent 2abe24b4b0
commit 263b0e480c
1 changed files with 11 additions and 17 deletions

View File

@ -478,26 +478,20 @@ static void *nt_vmcoreinfo(void *ptr)
static size_t nt_vmcoreinfo_size(void)
{
const char *name = "VMCOREINFO";
char nt_name[11];
Elf64_Nhdr note;
void *addr;
const char *name = VMCOREINFO_NOTE_NAME;
unsigned long size;
void *vmcoreinfo;
if (copy_oldmem_kernel(&addr, &S390_lowcore.vmcore_info, sizeof(addr)))
vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size);
if (vmcoreinfo)
return nt_size_name(size, name);
vmcoreinfo = get_vmcoreinfo_old(&size);
if (!vmcoreinfo)
return 0;
if (copy_oldmem_kernel(&note, addr, sizeof(note)))
return 0;
memset(nt_name, 0, sizeof(nt_name));
if (copy_oldmem_kernel(nt_name, addr + sizeof(note),
sizeof(nt_name) - 1))
return 0;
if (strcmp(nt_name, name) != 0)
return 0;
return nt_size_name(note.n_descsz, name);
kfree(vmcoreinfo);
return nt_size_name(size, name);
}
/*