Openmoko Bug #2199: bitbake wpa-supplicant-0.6.3 fails (OSError)

[Openmoko Public Trac]

#2199: bitbake wpa-supplicant-0.6.3 fails (OSError)
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    Reporter:  cfriedt                                   |        Owner:  openmoko-kernel
        Type:  defect                                    |       Status:  reopened       
    Priority:  normal                                    |    Milestone:                 
   Component:  System Software                           |      Version:                 
    Severity:  normal                                    |   Resolution:                 
    Keywords:  wpa-supplicant OSError permission denied  |     Haspatch:  0              
   Blockedby:                                            |    Estimated:                 
 Patchreview:                                            |     Blocking:                 
Reproducible:                                            |  
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Changes (by cfriedt):

  * keywords:  wpa-supplicant OSError => wpa-supplicant OSError permission
               denied


Comment:

 Python n00b or not, I think I may have found the fix. I can't be sure if
 this problem is actually in OpenEmbedded's package.bbclass, or whether it
 is an error or Python's os.stat(). My Python version is 2.5.2
 incidentally.

 My problem was this:

 1) os.stat() is called on a symbolic link

 /home/cfriedt/openmoko/oe/build/tm
 p/work/armv4t-angstrom-linux-gnueabi/wpa-
 supplicant-0.6.3-r3/image/etc/network/if-post-down.d/wpasupplicant

 which points to

 /etc/wpa_supplicant/ifupdown.sh

 2) os.stat(), for some reason, follows the symbolic link and attempts to
 perform another os.stat() on the target of the link (far before the
 os.readlink() function is called on the link itself)

 3) If the target of the link is contained within, or is itself, unreadable
 by the current user, then os.stat() throws an exception, errno.EACCES
 (13).

 I'm not going to bother submitting a patch for python, although I guess I
 could submit a bug report. There is, however, an attachment in this bug
 report that should fix OpenEmbedded.

 I gave it quite a bit of consideration, and I can't think of any case
 where this would actually pose a security threat in OE packages - it's
 more of glue code to handle a shortcoming in either python's or Linux's
 implementation of the stat() syscall.

-- 
Ticket URL: <https://docs.openmoko.org/trac/ticket/2199#comment:5>
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