qemu/0423-migration-fix-paramete...

57 lines
1.9 KiB
Diff

From: "Michael S. Tsirkin" <mst@redhat.com>
Date: Wed, 12 Nov 2014 11:44:39 +0200
Subject: [PATCH] migration: fix parameter validation on ram load
During migration, the values read from migration stream during ram load
are not validated. Especially offset in host_from_stream_offset() and
also the length of the writes in the callers of said function.
To fix this, we need to make sure that the [offset, offset + length]
range fits into one of the allocated memory regions.
Validating addr < len should be sufficient since data seems to always be
managed in TARGET_PAGE_SIZE chunks.
Fixes: CVE-2014-7840
Note: follow-up patches add extra checks on each block->host access.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
(cherry picked from commit 0be839a2701369f669532ea5884c15bead1c6e08)
Conflicts:
arch_init.c
---
arch_init.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch_init.c b/arch_init.c
index 23151b3..b6f7958 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -816,8 +816,8 @@ static inline void *host_from_stream_offset(QEMUFile *f,
uint8_t len;
if (flags & RAM_SAVE_FLAG_CONTINUE) {
- if (!block) {
- fprintf(stderr, "Ack, bad migration stream!\n");
+ if (!block || block->length <= offset) {
+ fprintf(stderr, "Ack, bad migration stream!");
return NULL;
}
@@ -829,8 +829,9 @@ static inline void *host_from_stream_offset(QEMUFile *f,
id[len] = 0;
QTAILQ_FOREACH(block, &ram_list.blocks, next) {
- if (!strncmp(id, block->idstr, sizeof(id)))
+ if (!strncmp(id, block->idstr, sizeof(id)) && block->length > offset) {
return memory_region_get_ram_ptr(block->mr) + offset;
+ }
}
fprintf(stderr, "Can't find block %s!\n", id);