Public bug reported: on our system (Ubuntu-Server 10.04) we set "sysctl -w kernel.pid_max = 4194304". When the pid counter is high, currently >3000000, then cron- apt terminates with a buffer overflow message:
root@sn:~# cron-apt *** buffer overflow detected ***: dotlockfile terminated ======= Backtrace: ========= /lib/libc.so.6(__fortify_fail+0x37)[0x7f2ae90547e7] /lib/libc.so.6(+0xfe6a0)[0x7f2ae90536a0] /lib/libc.so.6(+0xfdb09)[0x7f2ae9052b09] /lib/libc.so.6(_IO_default_xsputn+0xcc)[0x7f2ae8fcaf6c] /lib/libc.so.6(_IO_vfprintf+0x670)[0x7f2ae8f9aa10] /lib/libc.so.6(__vsprintf_chk+0x99)[0x7f2ae9052ba9] /lib/libc.so.6(__sprintf_chk+0x7f)[0x7f2ae9052aef] dotlockfile[0x401e6e] dotlockfile[0x40198a] /lib/libc.so.6(__libc_start_main+0xfd)[0x7f2ae8f73c4d] dotlockfile[0x4011f9] ======= Memory map: ======== 00400000-00403000 r-xp 00000000 fb:02 2104182 /usr/bin/dotlockfile 00602000-00603000 r--p 00002000 fb:02 2104182 /usr/bin/dotlockfile 00603000-00604000 rw-p 00003000 fb:02 2104182 /usr/bin/dotlockfile 01f80000-01fa1000 rw-p 00000000 00:00 0 [heap] 7f2ae8503000-7f2ae8519000 r-xp 00000000 fb:02 131128 /lib/libgcc_s.so.1 7f2ae8519000-7f2ae8718000 ---p 00016000 fb:02 131128 /lib/libgcc_s.so.1 7f2ae8718000-7f2ae8719000 r--p 00015000 fb:02 131128 /lib/libgcc_s.so.1 7f2ae8719000-7f2ae871a000 rw-p 00016000 fb:02 131128 /lib/libgcc_s.so.1 7f2ae871a000-7f2ae8726000 r-xp 00000000 fb:02 147406 /lib/libnss_files-2.11.1.so 7f2ae8726000-7f2ae8925000 ---p 0000c000 fb:02 147406 /lib/libnss_files-2.11.1.so 7f2ae8925000-7f2ae8926000 r--p 0000b000 fb:02 147406 /lib/libnss_files-2.11.1.so 7f2ae8926000-7f2ae8927000 rw-p 0000c000 fb:02 147406 /lib/libnss_files-2.11.1.so 7f2ae8927000-7f2ae8931000 r-xp 00000000 fb:02 147385 /lib/libnss_nis-2.11.1.so 7f2ae8931000-7f2ae8b30000 ---p 0000a000 fb:02 147385 /lib/libnss_nis-2.11.1.so 7f2ae8b30000-7f2ae8b31000 r--p 00009000 fb:02 147385 /lib/libnss_nis-2.11.1.so 7f2ae8b31000-7f2ae8b32000 rw-p 0000a000 fb:02 147385 /lib/libnss_nis-2.11.1.so 7f2ae8b32000-7f2ae8b49000 r-xp 00000000 fb:02 147369 /lib/libnsl-2.11.1.so 7f2ae8b49000-7f2ae8d48000 ---p 00017000 fb:02 147369 /lib/libnsl-2.11.1.so 7f2ae8d48000-7f2ae8d49000 r--p 00016000 fb:02 147369 /lib/libnsl-2.11.1.so 7f2ae8d49000-7f2ae8d4a000 rw-p 00017000 fb:02 147369 /lib/libnsl-2.11.1.so 7f2ae8d4a000-7f2ae8d4c000 rw-p 00000000 00:00 0 7f2ae8d4c000-7f2ae8d54000 r-xp 00000000 fb:02 147379 /lib/libnss_compat-2.11.1.so 7f2ae8d54000-7f2ae8f53000 ---p 00008000 fb:02 147379 /lib/libnss_compat-2.11.1.so 7f2ae8f53000-7f2ae8f54000 r--p 00007000 fb:02 147379 /lib/libnss_compat-2.11.1.so 7f2ae8f54000-7f2ae8f55000 rw-p 00008000 fb:02 147379 /lib/libnss_compat-2.11.1.so 7f2ae8f55000-7f2ae90cf000 r-xp 00000000 fb:02 147402 /lib/libc-2.11.1.so 7f2ae90cf000-7f2ae92ce000 ---p 0017a000 fb:02 147402 /lib/libc-2.11.1.so 7f2ae92ce000-7f2ae92d2000 r--p 00179000 fb:02 147402 /lib/libc-2.11.1.so 7f2ae92d2000-7f2ae92d3000 rw-p 0017d000 fb:02 147402 /lib/libc-2.11.1.so 7f2ae92d3000-7f2ae92d8000 rw-p 00000000 00:00 0 7f2ae92d8000-7f2ae92f8000 r-xp 00000000 fb:02 147370 /lib/ld-2.11.1.so 7f2ae94eb000-7f2ae94ee000 rw-p 00000000 00:00 0 7f2ae94f5000-7f2ae94f7000 rw-p 00000000 00:00 0 7f2ae94f7000-7f2ae94f8000 r--p 0001f000 fb:02 147370 /lib/ld-2.11.1.so 7f2ae94f8000-7f2ae94f9000 rw-p 00020000 fb:02 147370 /lib/ld-2.11.1.so 7f2ae94f9000-7f2ae94fa000 rw-p 00000000 00:00 0 7fff43082000-7fff430a3000 rw-p 00000000 00:00 0 [stack] 7fff431ff000-7fff43200000 r-xp 00000000 00:00 0 [vdso] ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall] Aborted root@sn:~# uname -a Linux sn 2.6.35-32-server #68~lucid1-Ubuntu SMP Wed Mar 28 18:33:00 UTC 2012 x86_64 GNU/Linux root@sn:~# ps PID TTY TIME CMD 3722057 pts/5 00:00:00 bash 3925974 pts/5 00:00:00 ps root@sn:~# strace -f -o out cron-apt *** buffer overflow detected ***: dotlockfile terminated ======= Backtrace: ========= /lib/libc.so.6(__fortify_fail+0x37)[0x7f27661f27e7] /lib/libc.so.6(+0xfe6a0)[0x7f27661f16a0] /lib/libc.so.6(+0xfdb09)[0x7f27661f0b09] /lib/libc.so.6(_IO_default_xsputn+0xcc)[0x7f2766168f6c] /lib/libc.so.6(_IO_vfprintf+0x670)[0x7f2766138a10] /lib/libc.so.6(__vsprintf_chk+0x99)[0x7f27661f0ba9] /lib/libc.so.6(__sprintf_chk+0x7f)[0x7f27661f0aef] dotlockfile[0x401e6e] dotlockfile[0x40198a] /lib/libc.so.6(__libc_start_main+0xfd)[0x7f2766111c4d] dotlockfile[0x4011f9] ======= Memory map: ======== 00400000-00403000 r-xp 00000000 fb:02 2104182 /usr/bin/dotlockfile 00602000-00603000 r--p 00002000 fb:02 2104182 /usr/bin/dotlockfile 00603000-00604000 rw-p 00003000 fb:02 2104182 /usr/bin/dotlockfile 01a13000-01a34000 rw-p 00000000 00:00 0 [heap] 7f27656a1000-7f27656b7000 r-xp 00000000 fb:02 131128 /lib/libgcc_s.so.1 7f27656b7000-7f27658b6000 ---p 00016000 fb:02 131128 /lib/libgcc_s.so.1 7f27658b6000-7f27658b7000 r--p 00015000 fb:02 131128 /lib/libgcc_s.so.1 7f27658b7000-7f27658b8000 rw-p 00016000 fb:02 131128 /lib/libgcc_s.so.1 7f27658b8000-7f27658c4000 r-xp 00000000 fb:02 147406 /lib/libnss_files-2.11.1.so 7f27658c4000-7f2765ac3000 ---p 0000c000 fb:02 147406 /lib/libnss_files-2.11.1.so 7f2765ac3000-7f2765ac4000 r--p 0000b000 fb:02 147406 /lib/libnss_files-2.11.1.so 7f2765ac4000-7f2765ac5000 rw-p 0000c000 fb:02 147406 /lib/libnss_files-2.11.1.so 7f2765ac5000-7f2765acf000 r-xp 00000000 fb:02 147385 /lib/libnss_nis-2.11.1.so 7f2765acf000-7f2765cce000 ---p 0000a000 fb:02 147385 /lib/libnss_nis-2.11.1.so 7f2765cce000-7f2765ccf000 r--p 00009000 fb:02 147385 /lib/libnss_nis-2.11.1.so 7f2765ccf000-7f2765cd0000 rw-p 0000a000 fb:02 147385 /lib/libnss_nis-2.11.1.so 7f2765cd0000-7f2765ce7000 r-xp 00000000 fb:02 147369 /lib/libnsl-2.11.1.so 7f2765ce7000-7f2765ee6000 ---p 00017000 fb:02 147369 /lib/libnsl-2.11.1.so 7f2765ee6000-7f2765ee7000 r--p 00016000 fb:02 147369 /lib/libnsl-2.11.1.so 7f2765ee7000-7f2765ee8000 rw-p 00017000 fb:02 147369 /lib/libnsl-2.11.1.so 7f2765ee8000-7f2765eea000 rw-p 00000000 00:00 0 7f2765eea000-7f2765ef2000 r-xp 00000000 fb:02 147379 /lib/libnss_compat-2.11.1.so 7f2765ef2000-7f27660f1000 ---p 00008000 fb:02 147379 /lib/libnss_compat-2.11.1.so 7f27660f1000-7f27660f2000 r--p 00007000 fb:02 147379 /lib/libnss_compat-2.11.1.so 7f27660f2000-7f27660f3000 rw-p 00008000 fb:02 147379 /lib/libnss_compat-2.11.1.so 7f27660f3000-7f276626d000 r-xp 00000000 fb:02 147402 /lib/libc-2.11.1.so 7f276626d000-7f276646c000 ---p 0017a000 fb:02 147402 /lib/libc-2.11.1.so 7f276646c000-7f2766470000 r--p 00179000 fb:02 147402 /lib/libc-2.11.1.so 7f2766470000-7f2766471000 rw-p 0017d000 fb:02 147402 /lib/libc-2.11.1.so 7f2766471000-7f2766476000 rw-p 00000000 00:00 0 7f2766476000-7f2766496000 r-xp 00000000 fb:02 147370 /lib/ld-2.11.1.so 7f2766689000-7f276668c000 rw-p 00000000 00:00 0 7f2766693000-7f2766695000 rw-p 00000000 00:00 0 7f2766695000-7f2766696000 r--p 0001f000 fb:02 147370 /lib/ld-2.11.1.so 7f2766696000-7f2766697000 rw-p 00020000 fb:02 147370 /lib/ld-2.11.1.so 7f2766697000-7f2766698000 rw-p 00000000 00:00 0 7fff3660b000-7fff3662c000 rw-p 00000000 00:00 0 [stack] 7fff36765000-7fff36766000 r-xp 00000000 00:00 0 [vdso] ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall] Aborted When we switch back to a small pid number e.g. by "sysctl -w kernel.pid_max = 32768" cron-apt works again. The Problem also just occurs if the pid counter reached high values. If pid_max is set high but the counter is still low the problem doesn't show up. ** Affects: cron-apt (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1011477 Title: cron-apt buffer overflow with high pid numbers To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cron-apt/+bug/1011477/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs