Applications that use libxcb 1.1 cannot open more than 1024 files

[Andrew Pollock]

Hi,

We have some internal 32-bit applications that end up with a lot of files open. If they in turn call a program that links with libxcb, more often than not, that program segfaults.

This has been determined to be because libxcb uses select() and the man page for select() says this:

"An fd_set is a fixed size buffer. Executing FD_CLR() or FD_SET() with a value of fd that is negative or is equal to or larger than FD_SETSIZE will result in undefined behavior. Moreover, POSIX requires fd to be a valid file descriptor."

Later versions of libxcb address this by using poll()

I'm attaching the patch that we are using internally against libxcb 1.1-1.1

If you make this SRU, please also ensure that the 32-bit version in ia32-libs gets updated.

[Andrew Pollock (apollock)]

Assigning to Timo as discussed via email

[Timo Aaltonen (tjaalton)]

the xid bug is #220628

[Timo Aaltonen (tjaalton)]

closing for karmic

[Timo Aaltonen (tjaalton)]

Uploaded to hardy-proposed.

[Martin Pitt (pitti)]

Accepted libxcb into hardy-proposed, the package will build now and be available in a few hours. Please test and give feedback here. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you in advance!

[Martin Pitt (pitti)]

Anyone who could test the packages in hardy-proposed?

[Andrew Pollock (apollock)]

We've only been affected by the 32-bit version on a 64-bit system, and I can't see a fixed ia32-libs in hardy-proposed

[Martin Pitt (pitti)]

This proposed update has been in hardy-proposed for almost half a year without any positive feedback, and it was reported to cause a regression in bug 220628. Therefore it was removed from hardy-proposed again.