i386: fix regression parsing multiboot initrd modules

The logic for parsing the multiboot initrd modules was messed up in

  commit 950c4e6c94
  Author: Daniel P. Berrangé <berrange@redhat.com>
  Date:   Mon Apr 16 12:17:43 2018 +0100

    opts: don't silently truncate long option values

Causing the length to be undercounter, and the number of modules over
counted. It also passes NULL to get_opt_value() which was not robust
at accepting a NULL value.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180514171913.17664-2-berrange@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Tested-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2018-05-14 18:19:11 +01:00 committed by Paolo Bonzini
parent 8449bcf949
commit 6e3ad3f0e3
2 changed files with 4 additions and 3 deletions

View File

@ -292,8 +292,7 @@ int load_multiboot(FWCfgState *fw_cfg,
cmdline_len += strlen(kernel_cmdline) + 1;
if (initrd_filename) {
const char *r = get_opt_value(initrd_filename, NULL);
cmdline_len += strlen(r) + 1;
mbs.mb_mods_avail = 1;
cmdline_len += strlen(initrd_filename) + 1;
while (1) {
mbs.mb_mods_avail++;
r = get_opt_value(r, NULL);

View File

@ -75,7 +75,9 @@ const char *get_opt_value(const char *p, char **value)
size_t capacity = 0, length;
const char *offset;
if (value) {
*value = NULL;
}
while (1) {
offset = qemu_strchrnul(p, ',');
length = offset - p;