[Patches] [ python-Patches-1704621 ] interpreter crash when multiplying large lists

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Patches item #1704621, was opened at 2007-04-20 18:17
Message generated for change (Comment added) made by jorend
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Category: Core (C code)
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Daniel Stutzbach (agthorr)
Assigned to: Nobody/Anonymous (nobody)
Summary: interpreter crash when multiplying large lists

Initial Comment:
Here's a succinct summary of the problem:

>>> x = [0] * 2**20
>>> x *= 2**20
Segmentation fault (core dumped)

>>> x = [0] * 2**20
>>> x * 2**20
[]
>>>

The problem is that list_repeat()'s check for an overflow is flawed, and list_inplace_repeat() doesn't check at all.  Attached is a patch that adds a correct check to both functions.  With the patch, both variations throw a MemoryError exception.  The patch is against Python 2.5, but should also fix 2.5.1/2.6/3.0.

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Comment By: Jason Orendorff (jorend)
Date: 2007-04-20 18:41

Message:
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Yes, I see it.  Patch looks good.  I haven't tested it.

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You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1704621&group_id=5470