From: "Michael S. Tsirkin" Date: Thu, 3 Apr 2014 19:51:42 +0300 Subject: [PATCH] vmstate: fix buffer overflow in target-arm/machine.c CVE-2013-4531 cpreg_vmstate_indexes is a VARRAY_INT32. A negative value for cpreg_vmstate_array_len will cause a buffer overflow. VMSTATE_INT32_LE was supposed to protect against this but doesn't because it doesn't validate that input is non-negative. Fix this macro to valide the value appropriately. The only other user of VMSTATE_INT32_LE doesn't ever use negative numbers so it doesn't care. Reported-by: Anthony Liguori Signed-off-by: Michael S. Tsirkin Signed-off-by: Juan Quintela (cherry picked from commit d2ef4b61fe6d33d2a5dcf100a9b9440de341ad62) --- savevm.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/savevm.c b/savevm.c index 9f7f668..ffc1a7c 100644 --- a/savevm.c +++ b/savevm.c @@ -1104,17 +1104,20 @@ const VMStateInfo vmstate_info_int32_equal = { .put = put_int32, }; -/* 32 bit int. See that the received value is the less or the same - than the one in the field */ +/* 32 bit int. Check that the received value is non-negative + * and less than or equal to the one in the field. + */ static int get_int32_le(QEMUFile *f, void *pv, size_t size) { - int32_t *old = pv; - int32_t new; - qemu_get_sbe32s(f, &new); + int32_t *cur = pv; + int32_t loaded; + qemu_get_sbe32s(f, &loaded); - if (*old <= new) + if (loaded >= 0 && loaded <= *cur) { + *cur = loaded; return 0; + } return -EINVAL; }