Starting about a day ago I' get a segmentation fault 99% of the time when I run an ls -l or ls -g command. ls by itself or ls -a work just fine. i thought maybe it was related to running the 2.6.7-1.494.2.2 kernel, but it also happens with 2.6.6-1.435.2.3. This is very strange. Can anyone enlighten me?

before you do anything else, check your system for rootkits...

http://www.rootkit.nl

http://www.chkrootkit.org

Thanks. I will check for a rootkit.
I also ran an strace ls -l and I found a number of 'file not found' problems related to local time. And just about a day ago I got "system-config-date 1.7.3.1-0.fc2.1.noarch" when I ran yum update. Seems like that could be related...

Well, chkrootkit says things are ok. This, of course, doesn't guarantee anything, but at least for now I'm going to proceed on the assumption that my problems are caused by something I did as opposed to something nefarious.

I have found that I'm also getting seg faults with vi. The only changes I've made recently were the update I mentioned in the first post and installing kde to play with under a different user name. Can anyone offer a suggestion on how to trace down this problem? I'm doing a bunch of googling, but so far I haven't found a solution.

I just recently started having the same problem. I have 2 linux servers, and one is manifesting the problem, and the other is not. I also fear I have been hacked, but as of yet have been unable to find too much out of the ordinary:

This is strace on the good system...

*****beginsnip
open("/usr/share/locale/en_US.UTF-8/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en_US.utf8/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en_US/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en.UTF-8/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en.utf8/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open(".", O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY) = 3
fstat64(3, {st_mode=S_IFDIR|0750, st_size=4096, ...}) = 0
fcntl64(3, F_SETFD, FD_CLOEXEC) = 0
getdents64(3, /* 58 entries */, 4096) = 2048
lstat64("squid.conf", {st_mode=S_IFREG|0644, st_size=113674, ...}) = 0
getxattr("squid.conf", "system.posix_acl_access", (nil), 0) = -1 EOPNOTSUPP (Operation not supported)
socket(PF_FILE, SOCK_STREAM, 0) = 4
connect(4, {sa_family=AF_FILE, path="/var/run/nscd/socket"}, 110) = -1 ENOENT (No such file or directory)
close(4) = 0
****snip ****
lstat64("..", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
getxattr("..", "system.posix_acl_access", (nil), 0) = -1 EOPNOTSUPP (Operation not supported)
****endsnip





and on the bad system
****beginsnip
open("/usr/share/locale/en_US.UTF-8/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en_US.utf8/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en_US/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en.UTF-8/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en.utf8/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en/LC_TIME/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open(".", O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY) = 3
fstat64(3, {st_mode=S_IFDIR|0750, st_size=4096, ...}) = 0
fcntl64(3, F_SETFD, FD_CLOEXEC) = 0
getdents64(3, /* 64 entries */, 4096) = 2152
lstat64("..", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
+++ killed by SIGSEGV +++
****endsnip


I don't know where to go from here though...

SOLVED

The prelinking database got screwed up.

Just run:
/etc/cron.daily/prelink
and watch your troubles go away.

(I figured this out by using rootkithunter.
Installed: ftp://ftp.webtrek.com/pub/rpms/rkhun...6-1.noarch.rpm
Ran: rkhunter -c
Got: dependency changed for ls error - THIS WAS THE ONLY ERROR I GOT
Ran: /etc/cron.daily/prelink
Problem went away.)

Glad to hear yours cleaned up so easily. I also tried that soultion after I got rootkithunter because it was reporting several "dependency" change errors. Unfortunately it didnt seem to work. I thought about it some more and rembered that my toddler had walked up and powered down my system in the middle of me dong stuff. At the time I thought I had come through ok, but given my sudden rash of problems decided maybe I hadn't. At any rate I broke down and did a reinstall just to make extra sure things were cool with my system (after backing up my user data). After that I immediately installed rootkithunter to keep tabs on things. So far so good.

One question, how long did it take for your /etc/cron.daily/prelink to run?

I ran it twice. It took about 2 minutes the first time, and a minute the second time.

I had a very stupid problem....
every time i try to run a application that only root can open i keep getting the same error
"Segmentation Fault"
After i run
/etc/cron.daily/prelink
it disappears... can u explain me this issue???
Thanks always trying to learn a bit more