Closed Bug 752662 Opened 8 years ago Closed 8 years ago

Graphite 2 use-after-free crash

Categories

(Core :: Graphics, defect)

x86_64
macOS
defect
Not set
critical

Tracking

()

VERIFIED FIXED
mozilla15
Tracking Status
firefox13 + affected
firefox14 + fixed
firefox15 --- fixed
firefox-esr10 --- unaffected

People

(Reporter: posidron, Assigned: jfkthame)

References

(Blocks 1 open bug)

Details

(4 keywords, Whiteboard: [asan][sg:high][advisory-tracking+])

Attachments

(3 files)

Attached file testcase
The testcase is reproducible with a ASAN enabled build. If necessary, reload the testcase a few times. 

If you have not a ASAN enabled build yet, follow the instructions described here: https://developer.mozilla.org/en/Building_Firefox_with_Address_Sanitizer
Attached file callstack
Fixed in repo. Keep 'em coming :)
Attachment #621912 - Flags: review?(jdaggett) → review+
Keywords: sec-high
Whiteboard: [asan][sec-critical] → [asan][sg:high]
https://hg.mozilla.org/mozilla-central/rev/8789a1dc555d
Assignee: nobody → jfkthame
Status: NEW → RESOLVED
Closed: 8 years ago
Resolution: --- → FIXED
Is the ESR10 branch affected by this sg:high?
No; the graphite lib isn't present there.
Verified fixed in my May 10 post-fix ASAN build on OS X.
Status: RESOLVED → VERIFIED
If we have graphite2 in Firefox 13 we need to uplift this patch.
Comment on attachment 621912 [details] [diff] [review]
patch, cherry-pick fix from graphite repository

[Approval Request Comment]
Bug caused by (feature/regressing bug #): graphite font-shaping library

User impact if declined: users who enable graphite may be vulnerable to a crash caused by a malicious/buggy font

Testing completed (on m-c, etc.): see comment #8

Risk to taking this patch (and alternatives if risky): minimal risk, just adds a missing bounds check

String or UUID changes made by this patch: none

Nominating this for aurora (14) on the basis of comment #9.

The patch here doesn't apply to beta (13), because we took a complete graphite refresh for mozilla-14 in bug 746975.

IMO, the security concern here is relatively minor, given that graphite is preffed off by default and only likely to be enabled by a small minority of users with a specific interest in trying it (primarily for "exotic" writing systems). I see no point in trying to backport just this specific patch to the mozilla-13 version; if we're sufficiently concerned about it, we should backport the complete graphite update (but personally I don't think it is important to do so for a preffed-off feature).
Attachment #621912 - Flags: approval-mozilla-aurora?
Comment on attachment 621912 [details] [diff] [review]
patch, cherry-pick fix from graphite repository

[Triage Comment]
Approving for Aurora 14 given the sg:high rating.
Attachment #621912 - Flags: approval-mozilla-aurora? → approval-mozilla-aurora+
Whiteboard: [asan][sg:high] → [asan][sg:high][advisory-tracking+]
Group: core-security
You need to log in before you can comment on or make changes to this bug.