tzik@ I wonder if you can take a look at this. I'm not sure. It might come from this CL (https://chromium.googlesource.com/chromium/src/+/27d1e313968955f1a120b65b31e316263365b1b3). But I'm not sure. Thanks

It's more likely r427556 format to initialize a member variable in PrintMsg_Print_Params. I'll double check and confirm in a bit.

The uninitialized variable is |scale_factor_| in printing/print_settings.h.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/614913eb9d85a921dc84ee66d72e128af2c23f3a

commit 614913eb9d85a921dc84ee66d72e128af2c23f3a
Author: rbpotter <rbpotter@chromium.org>
Date: Fri Oct 28 23:59:48 2016

Fix uninitialized memory bug from scaling addition

|scale_factor_| was not initialized in PrintSettings::Clear()
function like the other elements of PrintSettings. Fixed by initializing
the value to default (1.0). Uninitialized value was introduced
in commit https://chromium.googlesource.com/chromium/src/+/769ffdf779d83399a6f219e2637c6469ab94da0e

BUG= 659594 

Review-Url: https://codereview.chromium.org/2461083002
Cr-Commit-Position: refs/heads/master@{#428550}

[modify] https://crrev.com/614913eb9d85a921dc84ee66d72e128af2c23f3a/printing/print_settings.cc

ClusterFuzz has detected this issue as fixed in range 428482:428589.

Detailed report: https://cluster-fuzz.appspot.com/testcase?key=5272280965054464

Fuzzer: svg_xml_tokenfuzz
Job Type: linux_msan_chrome
Platform Id: linux

Crash Type: Use-of-uninitialized-value
Crash Address: 
Crash State:
  base::Pickle::WriteBytes
  IPC::ParamTraits<PrintMsg_Print_Params>::Write
  printing::PrintingMessageFilter::OnGetDefaultPrintSettingsReply
  
Recommended Security Severity: Low

Regressed: https://cluster-fuzz.appspot.com/revisions?job=linux_msan_chrome&range=427353:427578
Fixed: https://cluster-fuzz.appspot.com/revisions?job=linux_msan_chrome&range=428482:428589

Minimized Testcase (0.18 Kb): https://cluster-fuzz.appspot.com/download/AMIfv96OeSq62o_8Ajx4SD8PZwOJiZ5giFbJ_P7X23upO7TL2tbHFgM992H74Jp-2Gp0ezU3vegB-vtpXMuSeW_EyudrILl73Voph5H8KYW28dcq0KpqbMYJe4wmCIwILRDH5dSC4vATtCBnbv7D241f2VAKxaImyw?testcase_id=5272280965054464

Additional requirements: Requires Gestures

See https://dev.chromium.org/Home/chromium-security/bugs/reproducing-clusterfuzz-bugs 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 is verified as fixed, closing issue.

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

This bug has been closed for more than 14 weeks. Removing security view restrictions.

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