memory: fix segv on qemu_ram_free(block=0x0)

Since f1060c55bf, the pointer is directly passed to
qemu_ram_free(). However, on initialization failure, it may be called
with a NULL pointer. Return immediately in this case.

This fixes a SEGV when memory initialization failed, for example
permission denied on open backing store /dev/hugepages, with -object
memory-backend-file,mem-path=/dev/hugepages.

Program received signal SIGSEGV, Segmentation fault.
0x00005555556e67e7 in qemu_ram_free (block=0x0) at /home/elmarco/src/qemu/exec.c:1775

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1459250451-29984-1-git-send-email-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Marc-André Lureau 2016-03-29 13:20:51 +02:00 committed by Paolo Bonzini
parent 1b0d9b05d4
commit 85bc2a1512

4
exec.c
View file

@ -1773,6 +1773,10 @@ static void reclaim_ramblock(RAMBlock *block)
void qemu_ram_free(RAMBlock *block)
{
if (!block) {
return;
}
qemu_mutex_lock_ramlist();
QLIST_REMOVE_RCU(block, next);
ram_list.mru_block = NULL;