From: Viktor Prutyanov <viktor.prutyanov@phystech.edu>

Before this patch, if elf2dmp failed to find NT kernel PE magic in
allowed virtual address range, then it assumes NULL as NT kernel
address and cause segfault.

This patch fix the problem described above by checking NT kernel address
before futher processing.

Signed-off-by: Viktor Prutyanov <viktor.prutyanov@phystech.edu>
Message-Id: <20190219211936.6466-1-viktor.prutyanov@phystech.edu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 contrib/elf2dmp/main.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/contrib/elf2dmp/main.c b/contrib/elf2dmp/main.c
index 1a45eaf..1bfeb89 100644
--- a/contrib/elf2dmp/main.c
+++ b/contrib/elf2dmp/main.c
@@ -524,6 +524,12 @@ int main(int argc, char *argv[])
         }
     }
 
+    if (!nt_start_addr) {
+        eprintf("Failed to find NT kernel image\n");
+        err = 1;
+        goto out_ps;
+    }
+
     printf("KernBase = 0x%016"PRIx64", signature is \'%.2s\'\n", KernBase,
             (char *)nt_start_addr);
 
-- 
1.8.3.1