Fix a potential UAF with FPDFAvail_IsLinearized().

Fix a potential UAF with FPDFAvail_IsLinearized().

Cache the linearized result rather than recalculating it.

BUG=608778
Committed: https://pdfium.googlesource.com/pdfium/+/35c2100a5f6a466635bf99b4e7117d23aeb54d2c

[Lei Zhang, 2016-05-10 22:20:47]

thestig@chromium.org changed reviewers:
+ weili@chromium.org

[Wei Li, 2016-05-11 00:26:25]

https://codereview.chromium.org/1968743002/diff/1/core/fpdfapi/fpdf_parser/cp...
File core/fpdfapi/fpdf_parser/cpdf_data_avail.cpp (right):

https://codereview.chromium.org/1968743002/diff/1/core/fpdfapi/fpdf_parser/cp...
core/fpdfapi/fpdf_parser/cpdf_data_avail.cpp:854: m_pHintTables.reset();
Will we lose hint stream info then? Will we still need that info for subsequent
loading?

[Lei Zhang, 2016-05-11 01:16:21]

https://codereview.chromium.org/1968743002/diff/1/core/fpdfapi/fpdf_parser/cp...
File core/fpdfapi/fpdf_parser/cpdf_data_avail.cpp (right):

https://codereview.chromium.org/1968743002/diff/1/core/fpdfapi/fpdf_parser/cp...
core/fpdfapi/fpdf_parser/cpdf_data_avail.cpp:854: m_pHintTables.reset();
On 2016/05/11 00:26:25, Wei Li wrote:
> Will we lose hint stream info then? Will we still need that info for
subsequent
> loading?

Yes, and that's not optimal. See patch set 2 - use the cached result instead.
There's no point in reparsing the header again, right?

[Wei Li, 2016-05-11 16:54:30]

lgtm

[Lei Zhang, 2016-05-11 19:58:36]

Description was changed from

==========
Fix a potential UAF with FPDFAvail_IsLinearized().

BUG=608778
==========

to

==========
Fix a potential UAF with FPDFAvail_IsLinearized().

Cache the linearized result rather than recalculating it.

BUG=608778
==========

[Lei Zhang, 2016-05-11 19:58:39]

The CQ bit was checked by thestig@chromium.org

[commit-bot: I haz the power, 2016-05-11 19:58:47]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1968743002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1968743002/20001

[commit-bot: I haz the power, 2016-05-11 19:59:08]

Description was changed from

==========
Fix a potential UAF with FPDFAvail_IsLinearized().

Cache the linearized result rather than recalculating it.

BUG=608778
==========

to

==========
Fix a potential UAF with FPDFAvail_IsLinearized().

Cache the linearized result rather than recalculating it.

BUG=608778

Committed:
https://pdfium.googlesource.com/pdfium/+/35c2100a5f6a466635bf99b4e7117d23aeb5...
==========

[commit-bot: I haz the power, 2016-05-11 19:59:09]

Committed patchset #2 (id:20001) as
https://pdfium.googlesource.com/pdfium/+/35c2100a5f6a466635bf99b4e7117d23aeb5...