[v4,1/4] hmp: fix "dump-quest-memory" segfault (ppc)

Message ID 20170913142036.2469-2-lvivier@redhat.com
State New
Headers show
Series
  • hmp: fix "dump-quest-memory" segfault
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Commit Message

Laurent Vivier Sept. 13, 2017, 2:20 p.m.
Running QEMU with
    qemu-system-ppc64 -M none -nographic -m 256
and executing
    dump-guest-memory /dev/null 0 8192
results in segfault

Fix by checking if we have CPU, and exit with
error if there is no CPU:

    (qemu) dump-guest-memory /dev/null
    this feature or command is not currently supported

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
---
 target/ppc/arch_dump.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

Comments

David Gibson Sept. 14, 2017, 12:14 a.m. | #1
On Wed, Sep 13, 2017 at 04:20:33PM +0200, Laurent Vivier wrote:
> Running QEMU with
>     qemu-system-ppc64 -M none -nographic -m 256
> and executing
>     dump-guest-memory /dev/null 0 8192
> results in segfault
> 
> Fix by checking if we have CPU, and exit with
> error if there is no CPU:
> 
>     (qemu) dump-guest-memory /dev/null
>     this feature or command is not currently supported
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> Reviewed-by: Greg Kurz <groug@kaod.org>
> Reviewed-by: Thomas Huth <thuth@redhat.com>

Acked-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  target/ppc/arch_dump.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/target/ppc/arch_dump.c b/target/ppc/arch_dump.c
> index 8e9397aa58..95b9ab6f29 100644
> --- a/target/ppc/arch_dump.c
> +++ b/target/ppc/arch_dump.c
> @@ -224,8 +224,15 @@ typedef struct NoteFuncDescStruct NoteFuncDesc;
>  int cpu_get_dump_info(ArchDumpInfo *info,
>                        const struct GuestPhysBlockList *guest_phys_blocks)
>  {
> -    PowerPCCPU *cpu = POWERPC_CPU(first_cpu);
> -    PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
> +    PowerPCCPU *cpu;
> +    PowerPCCPUClass *pcc;
> +
> +    if (first_cpu == NULL) {
> +        return -1;
> +    }
> +
> +    cpu = POWERPC_CPU(first_cpu);
> +    pcc = POWERPC_CPU_GET_CLASS(cpu);
>  
>      info->d_machine = PPC_ELF_MACHINE;
>      info->d_class = ELFCLASS;

Patch

diff --git a/target/ppc/arch_dump.c b/target/ppc/arch_dump.c
index 8e9397aa58..95b9ab6f29 100644
--- a/target/ppc/arch_dump.c
+++ b/target/ppc/arch_dump.c
@@ -224,8 +224,15 @@  typedef struct NoteFuncDescStruct NoteFuncDesc;
 int cpu_get_dump_info(ArchDumpInfo *info,
                       const struct GuestPhysBlockList *guest_phys_blocks)
 {
-    PowerPCCPU *cpu = POWERPC_CPU(first_cpu);
-    PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
+    PowerPCCPU *cpu;
+    PowerPCCPUClass *pcc;
+
+    if (first_cpu == NULL) {
+        return -1;
+    }
+
+    cpu = POWERPC_CPU(first_cpu);
+    pcc = POWERPC_CPU_GET_CLASS(cpu);
 
     info->d_machine = PPC_ELF_MACHINE;
     info->d_class = ELFCLASS;