1197650 - crash in gfxFontGroup::FindNonItalicFaceForChar

Status: RESOLVED FIXED

(Core :: Graphics: Text, defect)

Description

[John Daggett (:jtd)]

Searching through gfx-related top crashers for 41.b builds, #9 is a null-deref within gfxFontGroup::FindNonItalicFaceForChar. The problem here is that the Valid() check already occurs within FindOrMakeFont. If !Valid() a nullptr is returned. So the code here just needs to do a null-check rather than calling Valid() again.

https://crash-stats.mozilla.com/report/index/bf1c51b5-5bcc-4bb8-be6f-62e1a2150818

Comment 1

[John Daggett (:jtd)]

Attachment: patch, null-check newly created font

Comment 2

[John Daggett (:jtd)]

Attachment: patch, skip duplicate call to Valid()

The Valid() check has already been done within FindOrMakeFont, so just pass the result up (either valid or null).

Comment 3

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/c9a6e3c257bc

Comment 4

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/c9a6e3c257bc

Comment 6

[(Away)]

This showed up on the beta 41 crash charts. Could you request an uplift?

Comment 7

[John Daggett (:jtd)]

Comment on attachment 8651570 [details] [diff] [review]
patch, skip duplicate call to Valid()

Approval Request Comment
[Feature/regressing bug #]: crasher caused by null dereference
[User impact if declined]: small number of crashes
[Describe test coverage new/current, TreeHerder]: landed on central monday
[Risks and why]: very minor fix
[String/UUID change made/needed]: none

Comment 8

[Ritu Kothari (:ritu) (Inactive, please n-i to RyanVM, jcristau, or pascal)]

Comment on attachment 8651570 [details] [diff] [review]
patch, skip duplicate call to Valid()

Crash fix that is simple and safe. Aurora42+, Beta41+.

Comment 9

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/releases/mozilla-aurora/rev/b46868d2fe62

Comment 10

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/releases/mozilla-beta/rev/9687a5c4b63d