From c7c95a2f14d94eb8213ce7cab03acdef40fed093 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Wed, 18 Sep 2019 15:10:06 +0100 Subject: [PATCH 2/4] hostmem-file: fix pmem file size check MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Stefan Hajnoczi Message-id: <20190918151007.27973-2-stefanha@redhat.com> Patchwork-id: 90763 O-Subject: [RHEL-AV-8.1.0 qemu-kvm PATCH 1/2] hostmem-file: fix pmem file size check Bugzilla: 1724008 1736788 RH-Acked-by: Paolo Bonzini RH-Acked-by: Philippe Mathieu-Daudé RH-Acked-by: Igor Mammedov RH-Acked-by: Eduardo Habkost Commit 314aec4a6e06844937f1677f6cba21981005f389 ("hostmem-file: reject invalid pmem file sizes") added a file size check that verifies the hostmem object's size parameter against the actual devdax pmem file. This is useful because getting the size wrong results in confusing errors inside the guest. However, the code doesn't work properly for files where struct stat::st_size is zero. Hostmem-file's ->alloc() function returns early without setting an Error, causing the following assertion failure: qemu/memory.c:2215: memory_region_get_ram_ptr: Assertion `mr->ram_block' failed. This patch handles the case where qemu_get_pmem_size() returns 0 but there is no error. Fixes: 314aec4a6e06844937f1677f6cba21981005f389 Signed-off-by: Stefan Hajnoczi Message-Id: <20190823135632.25010-1-stefanha@redhat.com> Signed-off-by: Eduardo Habkost (cherry picked from commit 7faae95ebc966c2981b78cf7c25009dfa32d4b72) Note that this commit will be effectively reverted by the next one but I backported it to avoid conflicts. Signed-off-by: Stefan Hajnoczi Signed-off-by: Danilo C. L. de Paula --- backends/hostmem-file.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c index 29e55c9..ecc15e3 100644 --- a/backends/hostmem-file.c +++ b/backends/hostmem-file.c @@ -67,12 +67,12 @@ file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp) uint64_t size; size = qemu_get_pmem_size(fb->mem_path, &local_err); - if (!size) { + if (local_err) { error_propagate(errp, local_err); return; } - if (backend->size > size) { + if (size && backend->size > size) { error_setg(errp, "size property %" PRIu64 " is larger than " "pmem file \"%s\" size %" PRIu64, backend->size, fb->mem_path, size); -- 1.8.3.1