Re: [PATCH 06/18] pstore: Extract common arguments into structure

[Kees Cook]

On Tue, Mar 7, 2017 at 8:22 AM, Namhyung Kim <namhyung@xxxxxxxxx> wrote:
> On Tue, Mar 7, 2017 at 6:55 AM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>> The read/mkfile pair pass the same arguments and should be cleared
>> between calls. Move to a structure and wipe it after every loop.
>>
>> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
>> ---
>>  fs/pstore/platform.c   | 55 +++++++++++++++++++++++++++-----------------------
>>  include/linux/pstore.h | 28 ++++++++++++++++++++++++-
>>  2 files changed, 57 insertions(+), 26 deletions(-)
>>
>> diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
>> index 320a673ecb5b..3fa1575a6e36 100644
>> --- a/fs/pstore/platform.c
>> +++ b/fs/pstore/platform.c
>> @@ -766,16 +766,9 @@ EXPORT_SYMBOL_GPL(pstore_unregister);
>>  void pstore_get_records(int quiet)
>>  {
>>         struct pstore_info *psi = psinfo;
>> -       char                    *buf = NULL;
>> -       ssize_t                 size;
>> -       u64                     id;
>> -       int                     count;
>> -       enum pstore_type_id     type;
>> -       struct timespec         time;
>> +       struct pstore_record    record = { .psi = psi, };
>>         int                     failed = 0, rc;
>> -       bool                    compressed;
>>         int                     unzipped_len = -1;
>> -       ssize_t                 ecc_notice_size = 0;
>>
>>         if (!psi)
>>                 return;
>> @@ -784,39 +777,51 @@ void pstore_get_records(int quiet)
>>         if (psi->open && psi->open(psi))
>>                 goto out;
>>
>> -       while ((size = psi->read(&id, &type, &count, &time, &buf, &compressed,
>> -                                &ecc_notice_size, psi)) > 0) {
>> -               if (compressed && (type == PSTORE_TYPE_DMESG)) {
>> +       while ((record.size = psi->read(&record.id, &record.type,
>> +                                &record.count, &record.time,
>> +                                &record.buf, &record.compressed,
>> +                                &record.ecc_notice_size,
>> +                                record.psi)) > 0) {
>> +               if (record.compressed &&
>> +                   record.type == PSTORE_TYPE_DMESG) {
>>                         if (big_oops_buf)
>> -                               unzipped_len = pstore_decompress(buf,
>> -                                                       big_oops_buf, size,
>> +                               unzipped_len = pstore_decompress(
>> +                                                       record.buf,
>> +                                                       big_oops_buf,
>> +                                                       record.size,
>>                                                         big_oops_buf_sz);
>>
>>                         if (unzipped_len > 0) {
>> -                               if (ecc_notice_size)
>> +                               if (record.ecc_notice_size)
>>                                         memcpy(big_oops_buf + unzipped_len,
>> -                                              buf + size, ecc_notice_size);
>> -                               kfree(buf);
>> -                               buf = big_oops_buf;
>> -                               size = unzipped_len;
>> -                               compressed = false;
>> +                                              record.buf + recorrecord.size,
>
> A typo on record.size.

Thanks! Yeah, 0-day noticed this too. I've refreshed the patches in my
tree with the correction now.

-Kees

-- 
Kees Cook
Pixel Security