linux-kernel - inotify_add_watch() returning ENOSPC in 2.6.24 [watch descriptor leak?]

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <ecb4efd10802051749n6a626e84k3ac8210aa2b5a446@mail.gmail.com>
Date:	Tue, 5 Feb 2008 20:49:42 -0500
From:	"Clem Taylor" <clem.taylor@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: inotify_add_watch() returning ENOSPC in 2.6.24 [watch descriptor leak?]

I'm trying to move a MIPS based embedded system from 2.6.16.16 to
2.6.24. Most things seem to be working, but I'm having troubles with
inotify. The code is using inotify to detect a file written to /tmp
(tmpfs). The writer creates a file with a temporary name and then
rename()s the tmp file over the file I'm monitoring.

With 2.6.16.16, everything works fine, but with 2.6.24, the inotify
process runs for a while (~100 events) and then inotify_add_watch()
returns ENOSPC. Once this happens, I can't add new watches, even if I
kill the process and restart it. fs.inotify.max_user_instances and
fs.inotify.max_user_watches are both 128, so I'd imagine I'm hitting
this limit. For some reason the watches aren't getting cleaned up
(even after the process is killed).

In a loop, the code is doing:
    wd = inotify_add_watch(fd, file, IN_CLOSE_WRITE|IN_DELETE_SELF|IN_ONESHOT);
    blocking read on notify fd

Has something changed in the inotify() API since 2.6.16.16, or could
this be a leak?

                                      --Clem
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/