Bug#521870: [libinotify-ocaml-dev] Bad string length

[Gregory BELLIER <dest@gatekeeper.fr>]

Subject: libinotify-ocaml-dev: Bug in file inotify.ml, bad string length
Package: libinotify-ocaml-dev
Version: 0.7
Severity: important

There is a bug in the file inotify.ml.
I contacted the author but he doesn't reply my emails.

There is a temporary buffer made of lots of \0.
The problem is that we create a new string based on this buffer. The len 
is wrong so the fresh string contains too much \0.
For example: say you're monitoring a directory then you create a new 
directory named "a".
Because of this event, inotify will notify that a new directory has been 
created. Its length ? 16 chars.
That's right 16 chars instead of 1. I noticed this error because of a 
badly working concat.

Here is a small working patch already submitted to the author :

Replace the old 'read' function by this one :

let read fd =
 let ss = struct_size () in
 let toread = to_read fd in
   
 let ret = ref [] in
 let buf = String.make toread '\000' in
 let toread = Unix.read fd buf 0 toread in
   
 let i = ref 0 in
   
   while !i < toread
   do
     let wd, l, cookie, len = convert (String.sub buf !i ss) in
     let s = if len > 0 then
   let str_tmp = (String.sub buf (!i + ss) len) in
   let len2 = (String.index str_tmp '\000') in
     Some (String.sub str_tmp 0 len2)
     else
   None
     in
   ret := (wd, l, cookie, s) :: !ret;
   i := !i + (ss + len);
   done;
   
   List.rev !ret


Gregory "Dest" BELLIER.



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