Bug 198437 - KASAN: memorize and print call_rcu stack
Summary: KASAN: memorize and print call_rcu stack
Status: NEW
Alias: None
Product: Memory Management
Classification: Unclassified
Component: Sanitizers (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: Dmitry Vyukov
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2018-01-10 14:26 UTC by Dmitry Vyukov
Modified: 2018-09-19 09:03 UTC (History)
1 user (show)

See Also:
Kernel Version: ALL
Tree: Mainline
Regression: No


Attachments

Description Dmitry Vyukov 2018-01-10 14:26:17 UTC
In kernel lots of objects are freed by rcu, in such cases free stack is close to useless, e.g.:
https://groups.google.com/forum/#!topic/syzkaller-bugs/2pLLqWLYweo

We should extend KASAN to be able to remember 1 or several aux stacks for each object in FIFO order, insert hooks that note aux stacks to call_rcu (and maybe timer/workqueue functions), and print aux stacks in reports.

Ideally, we don't increase alloc_info size for this. I think we need to get back to storing free_info inside of the object.

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