linux-stable/arch/x86
Mike Galbraith 5849cdf8c1 x86/crash: Fix crash_setup_memmap_entries() out-of-bounds access
Commit in Fixes: added support for kexec-ing a kernel on panic using a
new system call. As part of it, it does prepare a memory map for the new
kernel.

However, while doing so, it wrongly accesses memory it has not
allocated: it accesses the first element of the cmem->ranges[] array in
memmap_exclude_ranges() but it has not allocated the memory for it in
crash_setup_memmap_entries(). As KASAN reports:

  BUG: KASAN: vmalloc-out-of-bounds in crash_setup_memmap_entries+0x17e/0x3a0
  Write of size 8 at addr ffffc90000426008 by task kexec/1187

  (gdb) list *crash_setup_memmap_entries+0x17e
  0xffffffff8107cafe is in crash_setup_memmap_entries (arch/x86/kernel/crash.c:322).
  317                                      unsigned long long mend)
  318     {
  319             unsigned long start, end;
  320
  321             cmem->ranges[0].start = mstart;
  322             cmem->ranges[0].end = mend;
  323             cmem->nr_ranges = 1;
  324
  325             /* Exclude elf header region */
  326             start = image->arch.elf_load_addr;
  (gdb)

Make sure the ranges array becomes a single element allocated.

 [ bp: Write a proper commit message. ]

Fixes: dd5f726076 ("kexec: support for kexec on panic using new system call")
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Young <dyoung@redhat.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/725fa3dc1da2737f0f6188a1a9701bead257ea9d.camel@gmx.de
2021-04-20 17:32:46 +02:00
..
boot EFI updates collected by Ard Biesheuvel: 2020-12-24 12:40:07 -08:00
configs module: remove EXPORT_UNUSED_SYMBOL* 2021-02-08 12:28:07 +01:00
crypto crypto: aesni - release FPU during skcipher walk API calls 2021-01-22 14:58:04 +11:00
entry x86/sev-es: Introduce ip_within_syscall_gap() helper 2021-03-08 14:22:17 +01:00
events perf/x86/intel: Fix unchecked MSR access error caused by VLBR_EVENT 2021-03-16 21:44:39 +01:00
hyperv iommu/hyperv: setup an IO-APIC IRQ remapping domain for root partition 2021-02-11 08:47:07 +00:00
ia32 x86/ia32_signal: Propagate __user annotation properly 2020-12-11 19:44:31 +01:00
include Merge branch 'akpm' (patches from Andrew) 2021-04-09 17:06:32 -07:00
kernel x86/crash: Fix crash_setup_memmap_entries() out-of-bounds access 2021-04-20 17:32:46 +02:00
kvm KVM: VMX: Don't use vcpu->run->internal.ndata as an array index 2021-04-13 18:23:41 -04:00
lib x86/sev-es: Use __copy_from_user_inatomic() 2021-03-09 12:37:54 +01:00
math-emu
mm x86/mem_encrypt: Correct physical address calculation in __set_clr_pte_enc() 2021-03-23 11:59:45 +01:00
net bpf, x86: Validate computation of branch displacements for x86-32 2021-04-08 16:24:53 +02:00
pci Simple Firmware Interface (SFI) support removal for v5.12-rc1 2021-02-24 10:35:29 -08:00
platform module: remove never implemented MODULE_SUPPORTED_DEVICE 2021-03-17 13:16:18 -07:00
power clang-lto for v5.12-rc1 (part2) 2021-02-23 15:13:45 -08:00
purgatory crypto: sha - split sha.h into sha1.h and sha2.h 2020-11-20 14:45:33 +11:00
ras
realmode
tools Modules updates for v5.12 2021-02-23 10:15:33 -08:00
um um: remove process stub VMA 2021-02-12 21:37:38 +01:00
video
xen xen: branch for v5.12-rc5 2021-03-26 11:15:25 -07:00
.gitignore
Kbuild
Kconfig x86, kfence: enable KFENCE for x86 2021-02-26 09:41:02 -08:00
Kconfig.assembler
Kconfig.cpu
Kconfig.debug
Makefile x86/build: Turn off -fcf-protection for realmode targets 2021-03-23 16:36:01 +01:00
Makefile.um
Makefile_32.cpu