The following revision refers to this bug:
  https://pdfium.googlesource.com/pdfium/+/0dc8571d1354b8c319510be625a446218449f532

commit 0dc8571d1354b8c319510be625a446218449f532
Author: Nicolas Pena <npm@chromium.org>
Date: Thu May 11 20:01:33 2017

Do not use vector data() when it is empty

Before, all pointers were being initialized to 0. After raw pointers were
changed to vectors, data() was used in some cases, but now no longer returns
nullptr when it is supposed to. This CL fixes that.

Bug:  chromium:721417 
Change-Id: Ia31b75b18dc17d7eed48538145fe5d0d59668843
Reviewed-on: https://pdfium-review.googlesource.com/5353
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Nicolás Peña <npm@chromium.org>

[modify] https://crrev.com/0dc8571d1354b8c319510be625a446218449f532/core/fxcodec/codec/ccodec_gifmodule.cpp
[modify] https://crrev.com/0dc8571d1354b8c319510be625a446218449f532/core/fxcodec/lgif/cgifdecompressor.cpp
[modify] https://crrev.com/0dc8571d1354b8c319510be625a446218449f532/core/fxcodec/lgif/fx_gif.cpp

ClusterFuzz has detected this issue as fixed in range 471184:471219.

Detailed report: https://clusterfuzz.com/testcase?key=6306107244150784

Fuzzer: afl_pdf_codec_gif_fuzzer
Job Type: afl_chrome_asan
Platform Id: linux

Crash Type: Abrt
Crash Address: 0x03e9000041d3
Crash State:
  CCodec_ProgressiveDecoder::GifInputRecordPositionBuf
  CCodec_ProgressiveDecoder::GifInputRecordPositionBuf
  CGifDecompressor::GetRecordPosition
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=afl_chrome_asan&range=470825:470884
Fixed: https://clusterfuzz.com/revisions?job=afl_chrome_asan&range=471184:471219

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6306107244150784


See https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reproducing.md for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

ClusterFuzz testcase 6306107244150784 is verified as fixed, so closing issue.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.