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On Tuesday 19 June 2007 12:27:10 Jan-Hendrik Zab wrote: |
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> 'strace -f su - jonsnow': |
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> |
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> [pid 4117] execve("/bin/zsh", ["-su"], [/* 6 vars */]) = |
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> -1 EACCES (Permission denied) |
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Note that the trace clearly shows that /bin/zsh isn't returning an error code |
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(in which case pid 4117 would immediately die) but rather the execve call is |
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returning an error code and the fork()ed copy of su continues executing |
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(writes an error to stderr and then dies). |
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According to http://www.die.net/doc/linux/man/man2/execve.2.html EACCES is |
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only returned by this function for a few reasons: |
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1) Search permission is denied on a component of the path prefix of filename |
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or the name of a script interpreter. (See also path_resolution(2).) |
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(So, make sure /bin and / are executable by uid 1000.) |
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2) The file or a script interpreter is not a regular file. |
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(So, make sure /bin/zsh is not a symlink, evidently that doesn't work.) |
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3) Execute permission is denied for the file or a script or ELF interpreter. |
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(So, make sure that /bin/zsh and /lib/ld-linux.so* are executable. |
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If /bin/zsh is a script make sure the interpreter listed after #! is |
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executable. Proceed recursively if THAT is a script.) |
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(Also, is it possible that you don't have the right /lib/ld-linux.so? See the |
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above link for some detail [the paragraph just above RETURN VALUE]. ldd |
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should be able to show you which one you need.) |
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4) The file system is mounted noexec. |
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(So, make sure that you filesystem is currently mounted exec.) |
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If all of those check out, I think you'll have to "use the source, luke". |
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> Permissions of '/': |
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> |
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> drwxr-xr-x 20 root root 4096 2007-06-17 16:21 // |
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That looks a little weird, but only because of the extra '/'. |
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On my system: |
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$ ls -ld / |
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drwxr-xr-x 23 root root 664 2007-06-11 20:27 / |
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-- |
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Boyd Stephen Smith Jr. ,= ,-_-. =. |
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bss03@××××××××××.net ((_/)o o(\_)) |
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ICQ: 514984 YM/AIM: DaTwinkDaddy `-'(. .)`-' |
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http://iguanasuicide.org/ \_/ |
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