LinuxQuestions.org - Redhat system froze this morning.

My system freaked out this morning. Can someone tell me what is wrong?

from /var/log/messages:
Dec 26 16:00:47 javadial kernel: Unable to handle kernel NULL pointer dereference at virtual address 00000074
Dec 26 16:00:47 javadial kernel: printing eip:
Dec 26 16:00:47 javadial kernel: c0143c53
Dec 26 16:00:47 javadial kernel: *pde = 00000000
Dec 26 16:00:47 javadial kernel: Oops: 0000
Dec 26 16:00:47 javadial kernel: ipt_REJECT iptable_filter ip_tables autofs 8139too mii sg sr_mod ide-scsi scsi_mod ide-cd cdrom keybdev mousedev hid input usb-uhci usbcore ext3 jbd
Dec 26 16:00:47 javadial kernel: CPU: 0
Dec 26 16:00:47 javadial kernel: EIP: 0060:[<c0143c53>] Not tainted
Dec 26 16:00:47 javadial kernel: EFLAGS: 00010202
Dec 26 16:00:47 javadial kernel:
Dec 26 16:00:47 javadial kernel: EIP is at page_referenced [kernel] 0xe3 (2.4.20-8)
Dec 26 16:00:47 javadial kernel: eax: c145db38 ebx: 00000d78 ecx: 00000000 edx: 0008bb61
Dec 26 16:00:47 javadial kernel: esi: c030d24c edi: c111fb3c ebp: 00000003 esp: d7eb1f84
Dec 26 16:00:47 javadial kernel: ds: 0068 es: 0068 ss: 0068
Dec 26 16:00:47 javadial kernel: Process kscand/Normal (pid: 7, stackpage=d7eb1000)
Dec 26 16:00:47 javadial kernel: Stack: d684da00 00000000 00000001 d7eb1fb4 c122da20 c122da20 c030d24c c111fb3c
Dec 26 16:00:47 javadial kernel: 00000003 c013c68e d7eb0000 c0125ba0 00000001 00000003 d7eb0000 c030d100
Dec 26 16:00:47 javadial kernel: d7eb0000 c013d564 c030d100 00000003 00000001 c025ef1b 000009c4 c013d4b0
Dec 26 16:00:47 javadial kernel: Call Trace: [<c013c68e>] scan_active_list [kernel] 0x3e (0xd7eb1fa8))
Dec 26 16:00:47 javadial kernel: [<c0125ba0>] process_timeout [kernel] 0x0 (0xd7eb1fb0))
Dec 26 16:00:47 javadial kernel: [<c013d564>] kscand [kernel] 0xb4 (0xd7eb1fc8))
Dec 26 16:00:47 javadial kernel: [<c013d4b0>] kscand [kernel] 0x0 (0xd7eb1fe0))
Dec 26 16:00:47 javadial kernel: [<c010742d>] kernel_thread_helper [kernel] 0x5 (0xd7eb1ff0))
Dec 26 16:00:47 javadial kernel:
Dec 26 16:00:47 javadial kernel:
Dec 26 16:00:47 javadial kernel: Code: 8b 41 74 39 41 60 b8 01 00 00 00 0f 43 44 24 04 89 44 24 04
Dec 26 17:00:36 javadial kernel: ------------[ cut here ]------------
Dec 26 17:00:36 javadial kernel: kernel BUG at page_alloc.c:117!
Dec 26 17:00:36 javadial kernel: invalid operand: 0000
Dec 26 17:00:36 javadial kernel: ipt_REJECT iptable_filter ip_tables autofs 8139too mii sg sr_mod ide-scsi scsi_mod ide-cd cdrom keybdev mousedev hid input usb-uhci usbcore ext3 jbd
Dec 26 17:00:36 javadial kernel: CPU: 0
Dec 26 17:00:36 javadial kernel: EIP: 0060:[<c013e1c8>] Not tainted
Dec 26 17:00:36 javadial kernel: EFLAGS: 00010286
Dec 26 17:00:36 javadial kernel:
Dec 26 17:00:36 javadial kernel: EIP is at __free_pages_ok [kernel] 0x38 (2.4.20-8)
Dec 26 17:00:36 javadial kernel: eax: 00000012 ebx: c122da58 ecx: c122da74 edx: c13651cc
Dec 26 17:00:36 javadial kernel: esi: cafcbd78 edi: 00000000 ebp: c621c100 esp: d7eb1dec
Dec 26 17:00:36 javadial kernel: ds: 0068 es: 0068 ss: 0068
Dec 26 17:00:36 javadial kernel: Process sendmail (pid: 25724, stackpage=d7eb1000)
Dec 26 17:00:36 javadial kernel: Stack: c030d100 00000002 cafcba58 c013fbe5 c030d100 c1038030 c030d34c cafcbd78
Dec 26 17:00:36 javadial kernel: cafcbd78 00001000 c122da58 cafcbd78 00001000 09f53025 c012eb1c c122da58
Dec 26 17:00:36 javadial kernel: 00000000 c0131187 d734ba00 40000000 cafcbd78 00000000 00000001 40400000
Dec 26 17:00:36 javadial kernel: Call Trace: [<c013fbe5>] remove_exclusive_swap_page [kernel] 0x85 (0xd7eb1df8))
Dec 26 17:00:36 javadial kernel: [<c012eb1c>] __free_pte [kernel] 0x4c (0xd7eb1e24))
Dec 26 17:00:36 javadial kernel: [<c0131187>] zap_pte_range [kernel] 0x137 (0xd7eb1e30))
Dec 26 17:00:36 javadial kernel: [<c012f18b>] zap_page_range [kernel] 0xcb (0xd7eb1e58))
Dec 26 17:00:36 javadial kernel: [<c013270f>] exit_mmap [kernel] 0xaf (0xd7eb1e98))
Dec 26 17:00:36 javadial kernel: [<c011a27a>] mmput [kernel] 0x4a (0xd7eb1ebc))
Dec 26 17:00:36 javadial kernel: [<c011f6f1>] do_exit [kernel] 0xf1 (0xd7eb1ecc))
Dec 26 17:00:36 javadial kernel: [<c011f994>] do_group_exit [kernel] 0x54 (0xd7eb1ee8))
Dec 26 17:00:36 javadial kernel: [<c01278fd>] get_signal_to_deliver [kernel] 0x19d (0xd7eb1ef8))
Dec 26 17:00:36 javadial kernel: [<c01092f4>] do_signal [kernel] 0x64 (0xd7eb1f20))
Dec 26 17:00:36 javadial kernel: [<c015698d>] vfs_readdir [kernel] 0x9d (0xd7eb1f54))
Dec 26 17:00:36 javadial kernel: [<c0120645>] do_getitimer [kernel] 0x65 (0xd7eb1f60))
Dec 26 17:00:36 javadial kernel: [<c012082e>] do_setitimer [kernel] 0xae (0xd7eb1f74))
Dec 26 17:00:36 javadial kernel: [<c0127ad2>] sys_rt_sigprocmask [kernel] 0xf2 (0xd7eb1f90))
Dec 26 17:00:36 javadial kernel: [<c01299b5>] sys_setuid [kernel] 0xb5 (0xd7eb1fa0))
Dec 26 17:00:36 javadial kernel: [<c01171f0>] do_page_fault [kernel] 0x0 (0xd7eb1fb0))
Dec 26 17:00:36 javadial kernel: [<c01171f0>] do_page_fault [kernel] 0x0 (0xd7eb1fbc))
Dec 26 17:00:36 javadial kernel: [<c0109570>] signal_return [kernel] 0x14 (0xd7eb1fc0))
Dec 26 17:00:36 javadial kernel:
Dec 26 17:00:36 javadial kernel:
Dec 26 17:00:36 javadial kernel: Code: 0f 0b 75 00 2a ef 25 c0 8b 73 08 85 f6 0f 85 b4 02 00 00 8b

The system was pingable, but wasn't responding to ssh. It had kernel errors on the monitor and wasn't responding to the keyboard. It came up after a reboot, and seems to be working again.

The last login to this box was Dec 16th. It's been up for 2 months without any problems.

HP desktop with PIII 933 with 384 ram. "Linux version 2.4.20-8 (bhcompile@porky.devel.redhat.com) (gcc version 3.2.2 20030222 (Red Hat Linux 3.2.2-5)) #1 Thu Mar 13 17:54:28 EST 2003"

Bad memory or hard drive? Any help would be appreciated.

thanks,
-Mag