Re: acl length - revisited

[Jan Kopriva]

Just looked at what the server does, it returns E2BIG, I wonder where
that is mapped to the non-descriptive EINVAL error.
 

It is mapped in srvproc.cc. Lines bellow shows the place:
02871         if (AL_Internalize <cid:[EMAIL PROTECTED]>((AL_ExternalAccessList <cid:[EMAIL 
PROTECTED]>) AccessList <cid:[EMAIL PROTECTED]>->SeqBody, newACL) != 0) {
02872             SLog <cid:[EMAIL PROTECTED]>(0, "CheckSetACLSemantics: ACL 
internalize failed (%x.%x.%x)",
02873                     Fid <cid:[EMAIL PROTECTED]>.Volume <cid:[EMAIL PROTECTED]>, Fid 
<cid:[EMAIL PROTECTED]>.Vnode <cid:[EMAIL PROTECTED]>, Fid <cid:[EMAIL PROTECTED]>.Unique 
<cid:[EMAIL PROTECTED]>);
02874             return(EINVAL);
02875         }
In AL_Internalize, there is a following line:
if (p + m > AL_MaxExtEntries) return(-1);
That is why the execution in case of too big ACL, never gets to the code 
right
bellow the previous branch:

02876         if ((*newACL)->MySize + 4 > aCLSize) {
02877             SLog <cid:[EMAIL PROTECTED]>(0, "CheckSetACLSemantics: ACL too big 
(%x.%x.%x)",
02878                     Fid <cid:[EMAIL PROTECTED]>.Volume <cid:[EMAIL PROTECTED]>, Fid 
<cid:[EMAIL PROTECTED]>.Vnode <cid:[EMAIL PROTECTED]>, Fid <cid:[EMAIL PROTECTED]>.Unique 
<cid:[EMAIL PROTECTED]>);
02879             return(E2BIG);
02880         }
02881     }
and EINVAL is returned.
Which is why I think it is probably better to get the correct error code
propagated back from the server to cfs so that it can give a useful
response without having to rely on a hardcoded value.
Jan
 

I agree. I actually overlooked the second check in srvproc.cc :) However 
it is executed only
in case of correct ACL length thus noone sees E2BIG error. Also, my 
intention was not let the
cfs to perform the long data path if it is able to detect incorrect ACL 
length. But cfs is
not time critical and let the server take care about the return values 
is definitely better design.

I can add a function right before  AL_Internalize 
<cid:[EMAIL PROTECTED]>() that just checks for the length 
and returns the
E2BIG.  The second check can be wiped out.

Later
Jan