Commit Graph

3 Commits

Author SHA1 Message Date
Kostya Kortchinsky
ada2761407 [scudo] Fix an edge case in the secondary allocator
Summary:
s/CHECK_LT/CHECK_LE/ in the secondary allocator, as under certain circumstances
Ptr + Size can be equal to MapEnd. This edge case was not found by the current
tests, so those were extended to be able to catch that.

Reviewers: kcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D25101

llvm-svn: 282913
2016-09-30 19:57:21 +00:00
Kostya Kortchinsky
1da3ea561a [scudo] Fix a bug in the new Secondary Allocator
Summary:
GetActuallyAllocatedSize() was not accounting for the last page of the mapping
being a guard page, and was returning the wrong number of actually allocated
bytes, which in turn would mess up with the realloc logic. Current tests didn't
find this as the size exercised was only serviced by the Primary.

Correct the issue by subtracting PageSize, and update the realloc test to
exercise paths in both the Primary and the Secondary.

Reviewers: kcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D24787

llvm-svn: 282030
2016-09-20 22:17:59 +00:00
Kostya Serebryany
712fc9803a [sanitizer] Initial implementation of a Hardened Allocator
Summary:
This is an initial implementation of a Hardened Allocator based on Sanitizer Common's CombinedAllocator.
It aims at mitigating heap based vulnerabilities by adding several features to the base allocator, while staying relatively fast.
The following were implemented:
- additional consistency checks on the allocation function parameters and on the heap chunks;
- use of checksum protected chunk header, to detect corruption;
- randomness to the allocator base;
- delayed freelist (quarantine), to mitigate use after free and overall determinism.
Additional mitigations are in the works.

Reviewers: eugenis, aizatsky, pcc, krasin, vitalybuka, glider, dvyukov, kcc

Subscribers: kubabrecka, filcab, llvm-commits

Differential Revision: http://reviews.llvm.org/D20084

llvm-svn: 271968
2016-06-07 01:20:26 +00:00