• Anton Blanchard's avatar
    ppc64 sys_ipc breakage in 2.6.34-rc2 · 45575f5a
    Anton Blanchard authored
    I chased down a fail on ppc64 on 2.6.34-rc2 where an application that
    uses shared memory was getting a SEGV.
    
    Commit baed7fc9 ("Add generic sys_ipc
    wrapper") changed the second argument from an unsigned long to an int.
    When we call shmget the system call wrappers for sys_ipc will sign
    extend second (ie the size) which truncates it.  It took a while to
    track down because the call succeeds and strace shows the untruncated
    size :)
    
    The patch below changes second from an int to an unsigned long which
    fixes shmget on ppc64 (and I assume s390, sparc64 and mips64).
    Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
    --
    
    I assume the function prototypes for the other IPC methods would cause us
    to sign or zero extend second where appropriate (avoiding any security
    issues). Come to think of it, the syscall wrappers for each method should do
    that for us as well.
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    45575f5a
syscall.c 2.32 KB