• Julia Lawall's avatar
    drivers/net/wan: introduce missing kfree · 966a5d1b
    Julia Lawall authored
    Error handling code following a kmalloc should free the allocated data.
    
    The semantic match that finds the problem is as follows:
    (http://www.emn.fr/x-info/coccinelle/)
    
    // <smpl>
    @r exists@
    local idexpression x;
    statement S;
    expression E;
    identifier f,f1,l;
    position p1,p2;
    expression *ptr != NULL;
    @@
    
    x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
    ...
    if (x == NULL) S
    <... when != x
         when != if (...) { <+...x...+> }
    (
    x->f1 = E
    |
     (x->f1 == NULL || ...)
    |
     f(...,x->f1,...)
    )
    ...>
    (
     return \(0\|<+...x...+>\|ptr\);
    |
     return@p2 ...;
    )
    
    @script:python@
    p1 << r.p1;
    p2 << r.p2;
    @@
    
    print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
    // </smpl>
    Signed-off-by: default avatarJulia Lawall <julia@diku.dk>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    966a5d1b
hdlc_ppp.c 18.7 KB