• Andrey Vagin's avatar
    ipc: always handle a new value of auto_msgmni · f2f25589
    Andrey Vagin authored
    commit 1195d94e006b23c6292e78857e154872e33b6d7e upstream.
    
    proc_dointvec_minmax() returns zero if a new value has been set.  So we
    don't need to check all charecters have been handled.
    
    Below you can find two examples.  In the new value has not been handled
    properly.
    
    $ strace ./a.out
    open("/proc/sys/kernel/auto_msgmni", O_WRONLY) = 3
    write(3, "0\n\0", 3)                    = 2
    close(3)                                = 0
    exit_group(0)
    $ cat /sys/kernel/debug/tracing/trace
    
    $strace ./a.out
    open("/proc/sys/kernel/auto_msgmni", O_WRONLY) = 3
    write(3, "0\n", 2)                      = 2
    close(3)                                = 0
    
    $ cat /sys/kernel/debug/tracing/trace
    a.out-697   [000] ....  3280.998235: unregister_ipcns_notifier <-proc_ipcauto_dointvec_minmax
    
    Fixes: 9eefe520 ("ipc: do not use a negative value to re-enable msgmni automatic recomputin")
    Signed-off-by: 's avatarAndrey Vagin <avagin@openvz.org>
    Cc: Mathias Krause <minipli@googlemail.com>
    Cc: Manfred Spraul <manfred@colorfullife.com>
    Cc: Joe Perches <joe@perches.com>
    Cc: Davidlohr Bueso <davidlohr@hp.com>
    Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
    Signed-off-by: 's avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    f2f25589
ipc_sysctl.c 6.96 KB