795057 - SDP buffer not null-terminated if generated offer larger than 2048 bytes

Status: RESOLVED FIXED

(Core :: WebRTC, defect)

Description

[Randell Jesup [:jesup] (needinfo me)]

In local_video_test.html after the rev 2820 webrtc.org merge, windows crashes when it should put up the remote video element.  Mac and Linux seem to be ok.

Partly mangled output on one run may be a hint:

BORT: CRT ASSERT c:\tools\msvs!!! in executeNext: 10!!! Queue for {ae7e2108-75f7
\iea1-9f36-f4ee24c36c37} is currently: []\vc
lude\vector(932) : Assertion failed: vector subscript out of range

Will try to get more info once I rebuild.

Comment 1

[Randell Jesup [:jesup] (needinfo me)]

Attachment: Sanity-check attribute vector

Comment 2

[Randell Jesup [:jesup] (needinfo me)]

Comment on attachment 665716 [details] [diff] [review]
Sanity-check attribute vector

Note this doesn't solve the problem, merely sanity-checks to avoid crashes.

Comment 3

[Randell Jesup [:jesup] (needinfo me)]

13708[7268df0]: NrIceCtx(PC:70a32290): state 0->1
13708[7268df0]: NrIceCtx(PC:631ea093): state 0->1
13708[7268df0]: NrIceCtx(PC:70a32290): state 1->2
13708[7268df0]: Gathered all ICE candidates for 'PC:70a32290'
13708[7268df0]: NrIceCtx(PC:631ea093): state 1->2
13708[7268df0]: Gathered all ICE candidates for 'PC:631ea093'
0[1232b3f8]: Couldn't parse attributes for stream stream3'

Comment 4

[Randell Jesup [:jesup] (needinfo me)]

Additional debugging shows that the SDP buffer size is too small, and something isn't null-terminating when it hits the limit (perhaps adding ice candidates).

Bumping CCSIP_SDP_BUF_SIZE from 2048 to 4096 hides the problem on my laptop (it has wired, wireless and also a VM that appears as an interface, which may increase the number of ICE candidates).

Comment 5

[Ethan Hugg [:ehugg]]

This should be fixed in the patch to 798873 where the hard limit to SDP size has been removed.

Comment 6

[Henrik Skupin [:whimboo][⌚️UTC+2]]

(In reply to Randell Jesup [:jesup] from comment #0)
> In local_video_test.html after the rev 2820 webrtc.org merge, windows
> crashes when it should put up the remote video element.  Mac and Linux seem
> to be ok.

Where can I find that testcase? We re-imaged the alder branch so it's gone. It will be hard to create a testcase if we can't reproduce it.

Comment 7

[Randell Jesup [:jesup] (needinfo me)]

The old alder is mothballed at http://hg.mozilla.org/users/rjesup_wgate.com/alder-mothball

Comment 8

[Randell Jesup [:jesup] (needinfo me)]

Comment on attachment 665716 [details] [diff] [review]
Sanity-check attribute vector

Bump.  Belt and suspenders...

Comment 9

[Randell Jesup [:jesup] (needinfo me)]

Comment on attachment 665716 [details] [diff] [review]
Sanity-check attribute vector

Never mind, this was fixed another way