diff options
author | Michael S. Tsirkin <mst@redhat.com> | 2014-11-12 11:44:39 +0200 |
---|---|---|
committer | Amit Shah <amit.shah@redhat.com> | 2014-11-18 16:49:44 +0530 |
commit | 0be839a2701369f669532ea5884c15bead1c6e08 (patch) | |
tree | 6b8079fc2a2c8de297f60858e1becffbc93e5bab | |
parent | d6be29e3fb5659102ac0e48e295d177cb67e32c5 (diff) |
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>
-rw-r--r-- | arch_init.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch_init.c b/arch_init.c index 88a5ba0837..593a990b6d 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); |