Fix #70078: XSL callbacks with nodes as parameter leak memory #5130
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The fix for bug #49634 solved a double-free by copying the node with `xmlDocCopyNodeList()`, but the copied node is later freed by calling `xmlFreeNode()` instead of `xmlFreeNodeList()`, thus leaking memory. However, there is no need to treat the node as node list, i.e. to copy also the node's siblings; just creating a recursive copy of the node with `xmlDocCopyNode()` is sufficient, while that also avoids the leak.
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@m6w6, what do you think? |
Contributor
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@cmb69: Cool tnx :-) ... By the way: I never understood, why a recursive copy is made here at all ... this is also a performance issue when passing a bigger tree into a PHP function. In Bug #49634 it is not described, why this was made. But the comments describe the performance problem, too, after the fix. |
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@not-implemented, I first tried a shallow copy, but that caused xslt011.phpt to fail (the |
Contributor
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@cmb69: Ah okay, cool. Then this should be fine :-) Many thanks. |
Contributor
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Awesome, LGTM! |
nikic
approved these changes
Jan 30, 2020
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Thanks! Applied as 8226e70. |
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The fix for bug #49634 solved a double-free by copying the node with
xmlDocCopyNodeList(), but the copied node is later freed by callingxmlFreeNode()instead ofxmlFreeNodeList(), thus leaking memory.However, there is no need to treat the node as node list, i.e. to copy
also the node's siblings; just creating a recursive copy of the node
with
xmlDocCopyNode()is sufficient, while that also avoids the leak.