Part Number:AM3358
Tool/software: Linux
I am using the embedded Linux version 3.12.10 that comes with the TI SDK 7.0. I am trying to use PAM to increase the msgqueue value from 819200 to something higher for non-root users. I installed the latest version of Linux-PAM and setup the pam configuration files and the /etc/security/limits.conf file but the change in the msqqueue size is not taking affect. I did a:
strace -o ~/loglimit su - fireapp
To capture what is being executed when I do the su command and I see that a file called /etc/limits is being read:
open("/etc/limits", O_RDONLY|O_LARGEFILE) = 4
fstat64(4, {st_mode=S_IFREG|0644, st_size=1888, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb6
read(4, "# /etc/security/limits.conf\n#\n#E"..., 4096) = 1888
read(4, "", 4096) = 0
Looking at the /etc/limits file I see that it "could" do what PAM does, but it appears it does not support changing msqqueue:
# /etc/limits contains user resource limits.
# See limits(5).
#
# Format:
# <username> <limits-string>
#
# default entry is '*' for username
#
# Valid flags are:
# A: max address space (KB)
# C: max core file size (KB)
# D: max data size (KB)
# F: maximum filesize (KB)
# M: max locked-in-memory address space (KB) [only for root on Linux 2.0.x]
# N: max number of open files
# R: max resident set size (KB) [no effect on Linux 2.0.x]
# S: max stack size (KB)
# T: max CPU time (MIN)
# U: max number of processes
# L: max number of logins for this user
# I: max nice value (0..39 translates to 20..-19)
# O: max real time priority (0..MAX_RT_PRIO)
#
My questions are:
1). What is reading this /etc/limits file?
2). Is there a way of disabling it and using PAM?
3). Is there a newer version that supports msgqueues?
4). Is there a way to get both whatever this is and Linux-PAM working on the same board?