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Date:      Sun, 1 Mar 2009 22:48:18 +0000 (UTC)
From:      Robert Watson <rwatson@FreeBSD.org>
To:        cvs-src-old@freebsd.org
Subject:   cvs commit: src/sys/kern imgact_elf.c
Message-ID:  <200903012248.n21MmXlc004437@repoman.freebsd.org>

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rwatson     2009-03-01 22:48:18 UTC

  FreeBSD src repository

  Modified files:        (Branch: RELENG_7)
    sys/kern             imgact_elf.c 
  Log:
  SVN rev 189255 on 2009-03-01 22:48:18Z by rwatson
  
  Merge r187686 from head to stable/7:
  
    When a statically linked binary is executed (or at least, one without
    an interpreter definition in its program header), set the auxiliary
    ELF argument AT_BASE to 0 rather than to the address that we would
    have mapped the interpreter at if there had been one.
  
    The ELF ABI specifications appear to be ambiguous as to the desired
    behavior in this situation, as they define AT_BASE as the base address
    of the interpreter, but do not mention what to do if there is none.
    On Solaris, AT_BASE will be set to the base address of the static
    binary if there is no interpreter, and on Linux, AT_BASE is set to 0.
    We go with the Linux semantics as they are of more immediate utility
    and allow the early runtime environment to know that the kernel has
    not mapped an interpreter, but because AT_PHDR points at the ELF
    header for the running binary, it is still possible to retrieve all
    required mapping information when the process starts should it be
    required.  Either approach would be preferable to our current behavior
    of passing a pointer to an unmapped region of user memory as AT_BASE.
  
    Sponsored by: Google
  
  Revision   Changes    Path
  1.178.2.5  +2 -1      src/sys/kern/imgact_elf.c



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