qemu-iotests: s390x: fix test 049, reject negative sizes in QemuOpts

when creating an image qemu-img enable us specifying the size of the
image using -o size=xx options. But when we specify an invalid size
such as a negtive size then different platform gives different result.

parse_option_size() function in util/qemu-option.c will be called to
parse the size, a cast was called in the function to cast the input
(saved as a double in the function) size to an unsigned int64 value,
when the input is a negtive value or exceeds the maximum of uint64, then
the result is undefined.

According to C99 6.3.1.4, the result of converting a floating point
number to an integer that cannot represent the (integer part of) number
is undefined.  And sure enough the results are different on x86 and
s390.

C99 Language spec 6.3.1.4 Real floating and integers:
the result of this assignment/cast is undefined if the float is not
in the open interval (-1, U<type>_MAX+1).

Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Bo Tu <tubo@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Bo Tu 2015-07-03 15:28:49 +08:00 committed by Kevin Wolf
parent d8683155fa
commit 212789925e
2 changed files with 9 additions and 6 deletions

View File

@ -95,17 +95,15 @@ qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- -1024
qemu-img: Image size must be less than 8 EiB!
qemu-img create -f qcow2 -o size=-1024 TEST_DIR/t.qcow2
qemu-img: qcow2 doesn't support shrinking images yet
qemu-img: TEST_DIR/t.qcow2: Could not resize image: Operation not supported
Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=-1024 encryption=off cluster_size=65536 lazy_refcounts=off refcount_bits=16
qemu-img: Parameter 'size' expects a non-negative number below 2^64
qemu-img: TEST_DIR/t.qcow2: Invalid options for file format 'qcow2'
qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- -1k
qemu-img: Image size must be less than 8 EiB!
qemu-img create -f qcow2 -o size=-1k TEST_DIR/t.qcow2
qemu-img: qcow2 doesn't support shrinking images yet
qemu-img: TEST_DIR/t.qcow2: Could not resize image: Operation not supported
Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=-1024 encryption=off cluster_size=65536 lazy_refcounts=off refcount_bits=16
qemu-img: Parameter 'size' expects a non-negative number below 2^64
qemu-img: TEST_DIR/t.qcow2: Invalid options for file format 'qcow2'
qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- 1kilobyte
qemu-img: Invalid image size specified! You may use k, M, G, T, P or E suffixes for

View File

@ -180,6 +180,11 @@ void parse_option_size(const char *name, const char *value,
if (value != NULL) {
sizef = strtod(value, &postfix);
if (sizef < 0 || sizef > UINT64_MAX) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name,
"a non-negative number below 2^64");
return;
}
switch (*postfix) {
case 'T':
sizef *= 1024;