From 6d1f19c6c03cc1a2c6b8862a411db88d70f4e697 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 6 Dec 2016 16:18:45 +0100 Subject: [PATCH] fuse: fix clearing suid, sgid for chown() commit c01638f5d919728f565bf8b5e0a6a159642df0d9 upstream. Basically, the pjdfstests set the ownership of a file to 06555, and then chowns it (as root) to a new uid/gid. Prior to commit a09f99eddef4 ("fuse: fix killing s[ug]id in setattr"), fuse would send down a setattr with both the uid/gid change and a new mode. Now, it just sends down the uid/gid change. Technically this is NOTABUG, since POSIX doesn't _require_ that we clear these bits for a privileged process, but Linux (wisely) has done that and I think we don't want to change that behavior here. This is caused by the use of should_remove_suid(), which will always return 0 when the process has CAP_FSETID. In fact we really don't need to be calling should_remove_suid() at all, since we've already been indicated that we should remove the suid, we just don't want to use a (very) stale mode for that. This patch should fix the above as well as simplify the logic. Reported-by: Jeff Layton Signed-off-by: Miklos Szeredi Fixes: a09f99eddef4 ("fuse: fix killing s[ug]id in setattr") Reviewed-by: Jeff Layton [bwh: Backported to 3.2: adjust context, indentation] Signed-off-by: Ben Hutchings --- Reading git-format-patch failed