diff options
author | Markus Armbruster <armbru@redhat.com> | 2013-02-06 21:27:14 +0100 |
---|---|---|
committer | Anthony Liguori <aliguori@us.ibm.com> | 2013-02-06 16:35:17 -0600 |
commit | 82e59a676c01b3df3b53998d428d0a64a55f2439 (patch) | |
tree | c57a24a95c993f67f20b55a2d2510a06aacdcd1c | |
parent | 15af6321f4d1f90d0ae1b5cb05093c48b41c4533 (diff) |
qmp: Fix design bug and read beyond buffer in memchar-write
Command memchar-write takes data and size parameter. Begs the
question what happens when data doesn't match size.
With format base64, qmp_memchar_write() copies the full data argument,
regardless of size argument.
With format utf8, qmp_memchar_write() copies size bytes from data,
happily reading beyond data. Copies crap from the heap or even
crashes.
Drop the size parameter, and always copy the full data argument.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
-rw-r--r-- | hmp.c | 4 | ||||
-rw-r--r-- | qapi-schema.json | 4 | ||||
-rw-r--r-- | qemu-char.c | 8 | ||||
-rw-r--r-- | qmp-commands.hx | 4 |
4 files changed, 6 insertions, 14 deletions
@@ -664,13 +664,11 @@ void hmp_pmemsave(Monitor *mon, const QDict *qdict) void hmp_memchar_write(Monitor *mon, const QDict *qdict) { - uint32_t size; const char *chardev = qdict_get_str(qdict, "device"); const char *data = qdict_get_str(qdict, "data"); Error *errp = NULL; - size = strlen(data); - qmp_memchar_write(chardev, size, data, false, 0, &errp); + qmp_memchar_write(chardev, data, false, 0, &errp); hmp_handle_error(mon, &errp); } diff --git a/qapi-schema.json b/qapi-schema.json index cdd8384915..9e2cbbd1ae 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -346,8 +346,6 @@ # # @device: the name of the memory char device. # -# @size: the size to write in bytes. -# # @data: the source data write to memchar. # # @format: #optional the format of the data write to chardev 'memory', @@ -359,7 +357,7 @@ # Since: 1.4 ## { 'command': 'memchar-write', - 'data': {'device': 'str', 'size': 'int', 'data': 'str', + 'data': {'device': 'str', 'data': 'str', '*format': 'DataFormat'} } ## diff --git a/qemu-char.c b/qemu-char.c index ac5d62dd9a..9c1dd1326d 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -2753,9 +2753,8 @@ static bool qemu_is_chr(const CharDriverState *chr, const char *filename) return strcmp(chr->filename, filename); } -void qmp_memchar_write(const char *device, int64_t size, - const char *data, bool has_format, - enum DataFormat format, +void qmp_memchar_write(const char *device, const char *data, + bool has_format, enum DataFormat format, Error **errp) { CharDriverState *chr; @@ -2774,12 +2773,11 @@ void qmp_memchar_write(const char *device, int64_t size, return; } - write_count = (gsize)size; - if (has_format && (format == DATA_FORMAT_BASE64)) { write_data = g_base64_decode(data, &write_count); } else { write_data = (uint8_t *)data; + write_count = strlen(data); } ret = cirmem_chr_write(chr, write_data, write_count); diff --git a/qmp-commands.hx b/qmp-commands.hx index bbb21f3583..8468f1022d 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -467,7 +467,7 @@ EQMP { .name = "memchar-write", - .args_type = "device:s,size:i,data:s,format:s?", + .args_type = "device:s,data:s,format:s?", .mhandler.cmd_new = qmp_marshal_input_memchar_write, }, @@ -481,7 +481,6 @@ char device. Arguments: - "device": the name of the char device, must be unique (json-string) -- "size": the memory size, in bytes, should be power of 2 (json-int) - "data": the source data write to memory (json-string) - "format": the data format write to memory, default is utf8. (json-string, optional) @@ -491,7 +490,6 @@ Example: -> { "execute": "memchar-write", "arguments": { "device": foo, - "size": 8, "data": "abcdefgh", "format": "utf8" } } <- { "return": {} } |