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Diffstat (limited to 'lib/libkvm/kvm_amd64.c')
-rw-r--r--lib/libkvm/kvm_amd64.c176
1 files changed, 137 insertions, 39 deletions
diff --git a/lib/libkvm/kvm_amd64.c b/lib/libkvm/kvm_amd64.c
index 0e0366d..534323c 100644
--- a/lib/libkvm/kvm_amd64.c
+++ b/lib/libkvm/kvm_amd64.c
@@ -53,6 +53,7 @@ static char sccsid[] = "@(#)kvm_hp300.c 8.1 (Berkeley) 6/4/93";
#include <sys/user.h>
#include <sys/proc.h>
#include <sys/stat.h>
+#include <sys/mman.h>
#include <stdlib.h>
#include <unistd.h>
#include <nlist.h>
@@ -61,6 +62,8 @@ static char sccsid[] = "@(#)kvm_hp300.c 8.1 (Berkeley) 6/4/93";
#include <vm/vm.h>
#include <vm/vm_param.h>
+#include <machine/elf.h>
+
#include <limits.h>
#include "kvm_private.h"
@@ -71,36 +74,92 @@ static char sccsid[] = "@(#)kvm_hp300.c 8.1 (Berkeley) 6/4/93";
#endif
struct vmstate {
+ void *mmapbase;
+ size_t mmapsize;
pml4_entry_t *PML4;
};
+/*
+ * Map the ELF headers into the process' address space. We do this in two
+ * steps: first the ELF header itself and using that information the whole
+ * set of headers. (Taken from kvm_ia64.c)
+ */
+static int
+_kvm_maphdrs(kvm_t *kd, size_t sz)
+{
+ struct vmstate *vm = kd->vmst;
+
+ /* munmap() previous mmap(). */
+ if (vm->mmapbase != NULL) {
+ munmap(vm->mmapbase, vm->mmapsize);
+ vm->mmapbase = NULL;
+ }
+
+ vm->mmapsize = sz;
+ vm->mmapbase = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0);
+ if (vm->mmapbase == MAP_FAILED) {
+ _kvm_err(kd, kd->program, "cannot mmap corefile");
+ return (-1);
+ }
+ return (0);
+}
+
+/*
+ * Translate a physical memory address to a file-offset in the crash-dump.
+ * (Taken from kvm_ia64.c)
+ */
+static size_t
+_kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs)
+{
+ Elf_Ehdr *e = kd->vmst->mmapbase;
+ Elf_Phdr *p = (Elf_Phdr*)((char*)e + e->e_phoff);
+ int n = e->e_phnum;
+
+ while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz))
+ p++, n--;
+ if (n == 0)
+ return (0);
+ *ofs = (pa - p->p_paddr) + p->p_offset;
+ return (PAGE_SIZE - ((size_t)pa & PAGE_MASK));
+}
+
void
_kvm_freevtop(kvm_t *kd)
{
- if (kd->vmst != 0) {
- if (kd->vmst->PML4) {
- free(kd->vmst->PML4);
- }
- free(kd->vmst);
- }
+ struct vmstate *vm = kd->vmst;
+
+ if (vm->mmapbase != NULL)
+ munmap(vm->mmapbase, vm->mmapsize);
+ if (vm->PML4)
+ free(vm->PML4);
+ free(vm);
+ kd->vmst = NULL;
}
int
_kvm_initvtop(kvm_t *kd)
{
- struct vmstate *vm;
struct nlist nlist[2];
u_long pa;
u_long kernbase;
pml4_entry_t *PML4;
+ Elf_Ehdr *ehdr;
+ size_t hdrsz;
- vm = (struct vmstate *)_kvm_malloc(kd, sizeof(*vm));
- if (vm == 0) {
+ kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst));
+ if (kd->vmst == 0) {
_kvm_err(kd, kd->program, "cannot allocate vm");
return (-1);
}
- kd->vmst = vm;
- vm->PML4 = 0;
+ kd->vmst->PML4 = 0;
+
+ if (_kvm_maphdrs(kd, sizeof(Elf_Ehdr)) == -1)
+ return (-1);
+
+ ehdr = kd->vmst->mmapbase;
+ hdrsz = ehdr->e_phoff + ehdr->e_phentsize * ehdr->e_phnum;
+ if (_kvm_maphdrs(kd, hdrsz) == -1)
+ return (-1);
nlist[0].n_name = "kernbase";
nlist[1].n_name = 0;
@@ -128,12 +187,12 @@ _kvm_initvtop(kvm_t *kd)
_kvm_err(kd, kd->program, "cannot read KPML4phys");
return (-1);
}
- vm->PML4 = PML4;
+ kd->vmst->PML4 = PML4;
return (0);
}
static int
-_kvm_vatop(kvm_t *kd, u_long va, u_long *pa)
+_kvm_vatop(kvm_t *kd, u_long va, off_t *pa)
{
struct vmstate *vm;
u_long offset;
@@ -149,11 +208,9 @@ _kvm_vatop(kvm_t *kd, u_long va, u_long *pa)
u_long pdeindex;
u_long pteindex;
int i;
-
- if (ISALIVE(kd)) {
- _kvm_err(kd, 0, "kvm_vatop called in live kernel!");
- return((off_t)0);
- }
+ u_long a;
+ off_t ofs;
+ size_t s;
vm = kd->vmst;
offset = va & (PAGE_SIZE - 1);
@@ -163,20 +220,32 @@ _kvm_vatop(kvm_t *kd, u_long va, u_long *pa)
* not yet set) then return pa == va to avoid infinite recursion.
*/
if (vm->PML4 == 0) {
- *pa = va;
- return (PAGE_SIZE - offset);
+ s = _kvm_pa2off(kd, va, pa);
+ if (s == 0) {
+ _kvm_err(kd, kd->program,
+ "_kvm_vatop: bootstrap data not in dump");
+ goto invalid;
+ } else
+ return (PAGE_SIZE - offset);
}
pml4eindex = (va >> PML4SHIFT) & (NPML4EPG - 1);
pml4e = vm->PML4[pml4eindex];
- if (((u_long)pml4e & PG_V) == 0)
+ if (((u_long)pml4e & PG_V) == 0) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: pml4e not valid");
goto invalid;
+ }
pdpeindex = (va >> PDPSHIFT) & (NPDPEPG-1);
- pdpe_pa = ((u_long)pml4e & PG_FRAME) + (pdpeindex * sizeof(pdp_entry_t));
+ pdpe_pa = ((u_long)pml4e & PG_FRAME) +
+ (pdpeindex * sizeof(pdp_entry_t));
- /* XXX This has to be a physical address read, kvm_read is virtual */
- if (lseek(kd->pmfd, pdpe_pa, 0) == -1) {
+ s = _kvm_pa2off(kd, pdpe_pa, &ofs);
+ if (s <= sizeof pdpe) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: pdpe_pa not found");
+ goto invalid;
+ }
+ if (lseek(kd->pmfd, ofs, 0) == -1) {
_kvm_syserr(kd, kd->program, "_kvm_vatop: lseek pdpe_pa");
goto invalid;
}
@@ -184,24 +253,31 @@ _kvm_vatop(kvm_t *kd, u_long va, u_long *pa)
_kvm_syserr(kd, kd->program, "_kvm_vatop: read pdpe");
goto invalid;
}
- if (((u_long)pdpe & PG_V) == 0)
+ if (((u_long)pdpe & PG_V) == 0) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: pdpe not valid");
goto invalid;
-
+ }
pdeindex = (va >> PDRSHIFT) & (NPDEPG-1);
pde_pa = ((u_long)pdpe & PG_FRAME) + (pdeindex * sizeof(pd_entry_t));
- /* XXX This has to be a physical address read, kvm_read is virtual */
- if (lseek(kd->pmfd, pde_pa, 0) == -1) {
- _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek pde_pa");
+ s = _kvm_pa2off(kd, pde_pa, &ofs);
+ if (s <= sizeof pde) {
+ _kvm_syserr(kd, kd->program, "_kvm_vatop: pde_pa not found");
+ goto invalid;
+ }
+ if (lseek(kd->pmfd, ofs, 0) == -1) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: lseek pde_pa");
goto invalid;
}
if (read(kd->pmfd, &pde, sizeof pde) != sizeof pde) {
_kvm_syserr(kd, kd->program, "_kvm_vatop: read pde");
goto invalid;
}
- if (((u_long)pde & PG_V) == 0)
+ if (((u_long)pde & PG_V) == 0) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: pde not valid");
goto invalid;
+ }
if ((u_long)pde & PG_PS) {
/*
@@ -209,15 +285,25 @@ _kvm_vatop(kvm_t *kd, u_long va, u_long *pa)
*/
#define PAGE2M_MASK (NBPDR - 1)
#define PG_FRAME2M (~PAGE2M_MASK)
- *pa = ((u_long)pde & PG_FRAME2M) + (va & PAGE2M_MASK);
- return (NBPDR - (va & PAGE2M_MASK));
+ a = ((u_long)pde & PG_FRAME2M) + (va & PAGE2M_MASK);
+ s = _kvm_pa2off(kd, a, pa);
+ if (s == 0) {
+ _kvm_err(kd, kd->program,
+ "_kvm_vatop: 2MB page address not in dump");
+ goto invalid;
+ } else
+ return (NBPDR - (va & PAGE2M_MASK));
}
pteindex = (va >> PAGE_SHIFT) & (NPTEPG-1);
pte_pa = ((u_long)pde & PG_FRAME) + (pteindex * sizeof(pt_entry_t));
- /* XXX This has to be a physical address read, kvm_read is virtual */
- if (lseek(kd->pmfd, pte_pa, 0) == -1) {
+ s = _kvm_pa2off(kd, pte_pa, &ofs);
+ if (s <= sizeof pte) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: pte_pa not found");
+ goto invalid;
+ }
+ if (lseek(kd->pmfd, ofs, 0) == -1) {
_kvm_syserr(kd, kd->program, "_kvm_vatop: lseek");
goto invalid;
}
@@ -225,19 +311,31 @@ _kvm_vatop(kvm_t *kd, u_long va, u_long *pa)
_kvm_syserr(kd, kd->program, "_kvm_vatop: read");
goto invalid;
}
- if (((u_long)pte & PG_V) == 0)
+ if (((u_long)pte & PG_V) == 0) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: pte not valid");
goto invalid;
+ }
- *pa = ((u_long)pte & PG_FRAME) + offset;
- return (PAGE_SIZE - offset);
+ a = ((u_long)pte & PG_FRAME) + offset;
+ s = _kvm_pa2off(kd, a, pa);
+ if (s == 0) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: address not in dump");
+ goto invalid;
+ } else
+ return (PAGE_SIZE - offset);
invalid:
- _kvm_err(kd, 0, "invalid address (%x)", va);
+ _kvm_err(kd, 0, "invalid address (0x%lx)", va);
return (0);
}
int
-_kvm_kvatop(kvm_t *kd, u_long va, u_long *pa)
+_kvm_kvatop(kvm_t *kd, u_long va, off_t *pa)
{
+
+ if (ISALIVE(kd)) {
+ _kvm_err(kd, 0, "kvm_kvatop called in live kernel!");
+ return (0);
+ }
return (_kvm_vatop(kd, va, pa));
}
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