206815 - Purify UMR in PR_Poll's poll() call

Status: RESOLVED FIXED

(NSPR :: NSPR, defect)

Description

[Wan-Teh Chang]

In the PR_Poll implementation based on poll(), if a
PRPollDesc structure's fd field is NULL, we set the
corresponding pollfd structure's fd field to -1, but
we do not initialize its events field.  This is fine
because the poll man page says the events field is
ignored if the fd field is negative.  However,
apparently poll still reads the events field (at least
on Solaris), resulting in a UMR reported by Purify.

Comment 1

[Wan-Teh Chang]

Attachment: Proposed patch for NSPR TIP

Set the events field of a pollfd structure to 0 if we
set the fd field to -1.

Comment 2

[Wan-Teh Chang]

Attachment: Proposed patch for NSPR 4.1 branch

Same fix for the NSPR 4.1 branch.

Comment 3

[Wan-Teh Chang]

Comment on attachment 124025 [details] [diff] [review]
Proposed patch for NSPR 4.1 branch

Please ask your internal customer to test this patch
and see if it eliminates the UMR in PR_Poll.

Comment 4

[Kirk Erickson]

Comment on attachment 124023 [details] [diff] [review]
Proposed patch for NSPR TIP

Looks good.

Comment 5

[Kirk Erickson]

I'll create binaries and try contacting Fred Batty at Sun.

I greped for PR_Poll and found that indeed selfserv doesn't
call, but sslstrength and ssltap may.  Perhaps I can reproduce
with one of these in the meantime.

Comment 6

[Kirk Erickson]

This from Fred:

Hi, I have a lot of urgent work right now and probably won't be able to
verify this for several weeks. Why don't you go ahead and check in the fix,
and I'll mark the bug verified when I've had a chance to verify it. Thx

Comment 7

[Wan-Teh Chang]

Fixed on the NSPR tip (NSPR 4.4.1).