When access_process_vm is used in kernel/ptrace.c to write memory
to a debugged we were not correctly incrementing an address used to handle
memory faults. This meant that in some cases modifying memory in a child
process of a fork modified the memory of the parent as well. This patch
applies to version 2.4.17.
--- ptrace.c.orig Fri Feb 1 20:17:18 2002
+++ ptrace.c Sat Feb 2 00:53:43 2002
@@ -173,6 +173,7 @@
put_page(page);
len -= bytes;
buf += bytes;
+ addr += bytes;
}
up_read(&mm->mmap_sem);
mmput(mm);