• Nicolas Palix's avatar
    powerpc/chrp: Add missing of_node_put in pci.c · 29e931c0
    Nicolas Palix authored
    of_node_put is needed before discarding a value received from
    of_find_node_by_name, eg in error handling code or when the device
    node is no longer used.
    
    The semantic match that catches the bug is as follows:
    (http://www.emn.fr/x-info/coccinelle/)
    
    // <smpl>
    @r exists@
    local idexpression struct device_node *n;
    position p1, p2;
    statement S1,S2;
    expression E,E1;
    expression *ptr != NULL;
    @@
    
    (
    if (!(n@p1 = of_find_node_by_name(...))) S1
    |
    n@p1 = of_find_node_by_name(...)
    )
    <... when != of_node_put(n)
        when != if (...) { <+... of_node_put(n) ...+> }
        when != true !n  || ...
        when != n = E
        when != E = n
    if (!n || ...) S2
    ...>
    (
      return \(0\|<+...n...+>\|ptr\);
    |
    return@p2 ...;
    |
    n = E1
    |
    E1 = n
    )
    @script:python@
    p1 << r.p1;
    p2 << r.p2;
    @@
    
    print "* file: %s of_find_node_by_name %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
    // </smpl>
    Signed-off-by: default avatarNicolas Palix <npalix@diku.dk>
    Signed-off-by: default avatarJulia Lawall <julia@diku.dk>
    Acked-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
    Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
    29e931c0
pci.c 10.4 KB