qemu may pass us zero-length strings for smbios fields, when starting qemu this way ...
qemu -smbios type=1,version=,serial=test
... for example.
Today we don't specifically handle them and simply append them to the string list. Therefore we get two string-terminating zeros in a row. Result is that we by accident create a end-of-entry marker in the middle of the entry.
Fix this by handling zero-length strings like non-present strings.
Cc: armbru@redhat.com Signed-off-by: Gerd Hoffmann kraxel@redhat.com --- src/fw/smbios.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/src/fw/smbios.c b/src/fw/smbios.c index affb9be..d549329 100644 --- a/src/fw/smbios.c +++ b/src/fw/smbios.c @@ -133,20 +133,24 @@ get_external(int type, char **p, unsigned *nr_structs, do { \ size = get_field(type, offsetof(struct smbios_type_##type, \ field), end); \ - if (size > 0) { \ + if (size == 1) { \ + /* zero-length string, skip to avoid bogous end marker */ \ + p->field = 0; \ + } else if (size > 1) { \ end += size; \ + p->field = ++str_index; \ } else { \ memcpy(end, def, sizeof(def)); \ end += sizeof(def); \ + p->field = ++str_index; \ } \ - p->field = ++str_index; \ } while (0)
#define load_str_field_or_skip(type, field) \ do { \ size = get_field(type, offsetof(struct smbios_type_##type, \ field), end); \ - if (size > 0) { \ + if (size > 1) { \ end += size; \ p->field = ++str_index; \ } else { \
Gerd Hoffmann kraxel@redhat.com writes:
qemu may pass us zero-length strings for smbios fields, when starting qemu this way ...
qemu -smbios type=1,version=,serial=test
... for example.
Today we don't specifically handle them and simply append them to the string list. Therefore we get two string-terminating zeros in a row. Result is that we by accident create a end-of-entry marker in the middle of the entry.
And dmidecode screaming bloody murder :) More detail than you probably want to know at https://bugzilla.redhat.com/show_bug.cgi?id=1052837
Fix this by handling zero-length strings like non-present strings.
Cc: armbru@redhat.com Signed-off-by: Gerd Hoffmann kraxel@redhat.com
Spelling correction inline.
Reviewed-by: Markus Armbruster armbru@redhat.com
src/fw/smbios.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/src/fw/smbios.c b/src/fw/smbios.c index affb9be..d549329 100644 --- a/src/fw/smbios.c +++ b/src/fw/smbios.c @@ -133,20 +133,24 @@ get_external(int type, char **p, unsigned *nr_structs, do { \ size = get_field(type, offsetof(struct smbios_type_##type, \ field), end); \
if (size > 0) { \
if (size == 1) { \/* zero-length string, skip to avoid bogous end marker */ \
s/bogous/bogus/
p->field = 0; \} else if (size > 1) { \ end += size; \p->field = ++str_index; \ } else { \ memcpy(end, def, sizeof(def)); \ end += sizeof(def); \p->field = ++str_index; \ } \
p->field = ++str_index; \#define load_str_field_or_skip(type, field) \ do { \ size = get_field(type, offsetof(struct smbios_type_##type, \ field), end); \
if (size > 0) { \
if (size > 1) { \ end += size; \ p->field = ++str_index; \ } else { \
On Tue, Jan 21, 2014 at 01:24:02PM +0100, Gerd Hoffmann wrote:
qemu may pass us zero-length strings for smbios fields, when starting qemu this way ...
qemu -smbios type=1,version=,serial=test
... for example.
Today we don't specifically handle them and simply append them to the string list. Therefore we get two string-terminating zeros in a row. Result is that we by accident create a end-of-entry marker in the middle of the entry.
Fix this by handling zero-length strings like non-present strings.
Looks okay to me.
I wish we could get all of the smbios stuff moved to qemu.
-Kevin
-
Gerd Hoffmann -
Kevin O'Connor -
Markus Armbruster