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From 0be839a2701369f669532ea5884c15bead1c6e08 Mon Sep 17 00:00:00 2001
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
Upstream-Status: Backport
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>
Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
---
arch_init.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch_init.c b/arch_init.c
index 88a5ba0..593a990 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -1006,7 +1006,7 @@ static inline void *host_from_stream_offset(QEMUFile *f,
uint8_t len;
if (flags & RAM_SAVE_FLAG_CONTINUE) {
- if (!block) {
+ if (!block || block->length <= offset) {
error_report("Ack, bad migration stream!");
return NULL;
}
@@ -1019,8 +1019,9 @@ 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;
+ }
}
error_report("Can't find block %s!", id);
--
1.9.1
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