1491783 - Lighten file sharing mode during SignedBinary::VerifySignature

Status: RESOLVED FIXED

(Firefox :: General, enhancement, P2)

Description

[Carl Corcoran [:ccorcoran]]

Right now we currently only have FILE_SHARE_READ sharing mode (https://searchfox.org/mozilla-central/rev/bdc89dfd7869e418d788b28eb60ab8d94e708a15/mozglue/build/Authenticode.cpp#268), but I propose adding FILE_SHARE_DELETE | FILE_SHARE_WRITE, to slightly reduce impact.

The specific need is related to interaction between bug 1435827 and toolkit/components/ctypes/tests/chrome/test_ctypes.xul. This test attempts to delete a DLL that was loaded into the process, but bug 1435827 is at the same time examining its digital signature, causing the delete to fail.

Adding the appropriate file sharing mode will allow the file to be deleted more often. Though the later call to WinVerifyTrust() internally maps a view of the file with PAGE_READ_EXECUTE which also causes the delete to fail, but that can't be prevented.

We already do sufficient error checking, so just adding the flags appears to work fine.

Comment 1

[Carl Corcoran [:ccorcoran]]

Attachment: Bug 1491783: Allow file delete and write during VerifySignature;r=aklotz

Comment 2

[(No longer employed by Mozilla) Aaron Klotz]

Comment on attachment 9009568 [details]
Bug 1491783: Allow file delete and write during VerifySignature;r=aklotz

Aaron Klotz [:aklotz] has approved the revision.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/45ae214ae159
Allow file delete and write during VerifySignature;r=aklotz

Comment 4

[Arthur Iakab [arthur_iakab]]

https://hg.mozilla.org/mozilla-central/rev/45ae214ae159