Searched hist:c4fa6d7c5971baa45eca4f81b8f100299848486a (Results 1 – 1 of 1) sorted by relevance
/openbmc/linux/fs/nfsd/ |
H A D | vfs.c | diff c4fa6d7c5971baa45eca4f81b8f100299848486a Wed Dec 11 04:16:36 CST 2013 Stanislav Kholmanskikh <stanislav.kholmanskikh@oracle.com> nfsd: revoking of suid/sgid bits after chown() in a consistent way
There is an inconsistency in the handling of SUID/SGID file bits after chown() between NFS and other local file systems.
Local file systems (for example, ext3, ext4, xfs, btrfs) revoke SUID/SGID bits after chown() on a regular file even if the owner/group of the file has not been changed:
~# touch file; chmod ug+s file; chmod u+x file ~# ls -l file -rwsr-Sr-- 1 root root 0 Dec 6 04:49 file ~# chown root file; ls -l file -rwxr-Sr-- 1 root root 0 Dec 6 04:49 file
but NFS doesn't do that:
~# touch file; chmod ug+s file; chmod u+x file ~# ls -l file -rwsr-Sr-- 1 root root 0 Dec 6 04:49 file ~# chown root file; ls -l file -rwsr-Sr-- 1 root root 0 Dec 6 04:49 file
NFS does that only if the owner/group has been changed:
~# touch file; chmod ug+s file; chmod u+x file ~# ls -l file -rwsr-Sr-- 1 root root 0 Dec 6 05:02 file ~# chown bin file; ls -l file -rwxr-Sr-- 1 bin root 0 Dec 6 05:02 file
See: http://pubs.opengroup.org/onlinepubs/9699919799/functions/chown.html
"If the specified file is a regular file, one or more of the S_IXUSR, S_IXGRP, or S_IXOTH bits of the file mode are set, and the process has appropriate privileges, it is implementation-defined whether the set-user-ID and set-group-ID bits are altered."
So both variants are acceptable by POSIX.
This patch makes NFS to behave like local file systems.
Signed-off-by: Stanislav Kholmanskikh <stanislav.kholmanskikh@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
|