[poppler] Bogus memory allocation size

[suzuki toshiya]

Thanks, when I work for another issue, I will try to use git bisect.

I found the issue starts since:
commit b505920db6d3dac58c7e9f4f8917f4c4449b08a0
Merge: 9250449 a631281
Author: Albert Astals Cid <aacid at kde.org>
Date:   Tue Feb 14 19:18:54 2012 +0100

    Merge remote-tracking branch 'origin/xpdf303merge'

    Conflicts:
        utils/HtmlOutputDev.cc
        utils/HtmlOutputDev.h

However, I don't think 0.18.x is good and 0.19.x is bad.
I'm afraid that some overflow error occurs in 0.18.x but ignored silently.
I will check how the error occurs.

Regards,
mpsuzuki


Reece Dunn wrote:
> On 5 May 2012 08:13, suzuki toshiya <mpsuzuki at hiroshima-u.ac.jp> wrote:
>> I'm quite sorry! My posts assuming the error is 64-bit CPU specific
>> were wrong. I could reproduce the error on Linux i386 (I was testing
>> wrong revisions). I found 0.19.4 - 0.19.0 have this issue, but 0.18.4
>> does not have. Now I'm trying to find when this issue began.
> 
> On one of the linux boxes, you can do a git bisect to locate the issue quicker:
> 
> 1. Initial setup:
> 
> # Clone the git repository:
> git clone git://git.freedesktop.org/git/poppler/poppler
> 
> # Get the 0.19.0 release (first known revision containing the issue):
> git checkout poppler-0.19.0
> 
> # Start the bisect
> git bisect start
> 
> # Inform git that poppler-0.19.0 has the issue
> git bisect bad
> 
> # Get the 0.18.4 release (first known revision not containing the issue):
> git checkout poppler-0.18.4
> 
> # Inform git that poppler-0.18.4 does not have the issue
> git bisect good
> 
> 2. Build the current revision:
> 
> # Clean the poppler directory of build files
> git clean -fxd
> 
> # Build poppler
> ./autogen
> ./configure
> make
> 
> # Run your test using the built poppler
> ...
> 
> # If the revision contains the bug, run:
> git bisect bad
> # ... and go back to step 2
> 
> # If the revision does not contain the bug, run:
> git bisect good
> # ... and go back to step 2
> 
> # If the bisect has finished, that commit is the problem commit
> # Note the sha1 of the commit and go to step 3
> export BAD_COMMIT=<sha1 of commit bisect reports>
> 
> 3. Verify that reverting the commit fixes the issue
> 
> # Stop the bisect operation
> git bisect reset
> 
> # Go to the master (main) branch
> git checkout master
> 
> # Clean the poppler directory of build files
> git clean -fxd
> 
> # Build poppler
> ./autogen
> ./configure
> make
> 
> # Run your test using the built poppler (should fail)
> ...
> 
> # Revert the bad commit
> git revert ${BAD_COMMIT}
> 
> # Clean the poppler directory of build files
> git clean -fxd
> 
> # Build poppler
> ./autogen
> ./configure
> make
> 
> # Run your test using the built poppler (should pass)
> ...
> 
> 4. Report the bad commit
> 
> # Get the bad commit
> git show ${BAD_COMMIT} > bad-commit.diff
> 
> # View the bad commit
> cat bad-commit.diff
> 
> Thanks,
>  - Reece