[BProc] getpwuid and getgrgid bombing

[Daniel W. <wid...@ci...>]

#include <stdio.h>
#include <sys/bproc.h>
#include <pwd.h>
#include <sys/types.h>

main() {
        struct passwd *pwent = getpwuid(0);
        printf("%s\n",pwent->pw_name);
}


# bpsh 0 ./a.out
bpsh: Child process exited abnormally.


Same for getgrgid().  This is the problem to which Nic Henke was referring on
5/10 on this mailing list.  Apologies if this bug is already known and
listed.  The reason we're using this: pam_bproc module for access control.


Any ideas?  How do I go about debugging bpsh calls in general?  strace output
on master doesn't seem promising.  strace -f gives:

[root@alpha pam_bproc]# strace -f -o bpsh.out bpsh 0 ./a.out
Process 9229 attached
Process 9228 suspended

and bpsh.out ends in:

[pid  8940] open("/etc/ld.so.cache", O_RDONLY) = 3
[pid  8940] fstat64(3, {st_mode=S_IFREG|0644, st_size=16199, ...}) = 0
[pid  8940] old_mmap(NULL, 16199, PROT_READ, MAP_PRIVATE, 3, 0) = 0x40018000
[pid  8940] close(3)                    = 0
[pid  8940] open("/lib/libnss_files.so.2", O_RDONLY) = 3
[pid  8940] read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\200\0"..., 1024) = 1024
[pid  8940] fstat64(3, {st_mode=S_IFREG|0755, st_size=261460, ...}) = 0
[pid  8940] old_mmap(NULL, 42408, PROT_READ|PROT_EXEC, MAP_PRIVATE, 3, 0) = 0x4015b000
[pid  8940] mprotect(0x40165000, 1448, PROT_NONE) = 0
[pid  8940] old_mmap(0x40165000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED, 3, 0x9000) = 0x40165000
[pid  8940] close(3)                    = 0
[pid  8940] munmap(0x40018000, 16199)   = 0
[pid  8940] --- SIGSEGV (Segmentation fault) ---
[pid  8938] <... select resumed> )      = 2 (in [4 5], left {299, 640000})
[pid  8938] rt_sigprocmask(SIG_BLOCK, [CHLD], NULL, 8) = 0
[pid  8938] close(4)                    = 0
[pid  8938] read(5, "", 4096)           = 0
[pid  8938] close(5)                    = 0
[pid  8938] rt_sigprocmask(SIG_UNBLOCK, [CHLD], NULL, 8) = 0
[pid  8938] select(7, [0 3 6], [], NULL, {300, 0}) = 1 (in [6], left {300, 0})
[pid  8938] rt_sigprocmask(SIG_BLOCK, [CHLD], NULL, 8) = 0
[pid  8938] read(6, "", 4096)           = 0
[pid  8938] close(6)                    = 0
[pid  8938] wait4(-1,  <unfinished ...>
[pid  8940] +++ killed by SIGSEGV +++


Thanks,
Dan W.

-- 
-- Daniel Widyono                      http://www.cis.upenn.edu/~widyono
-- Linux Cluster Group,   CIS Dept.,  SEAS,   University of Pennsylvania
-- Mail: Rm 556, CIS Dept   200 S 33rd St         Philadelphia, PA 19104