From 550a7d3bc0c4049ef8d36ff4d9ed7082ee8cb5ec Mon Sep 17 00:00:00 2001 From: Vivek Goyal Date: Thu, 25 Mar 2021 11:18:23 -0400 Subject: fuse: add a flag FUSE_SETXATTR_ACL_KILL_SGID to kill SGID When posix access ACL is set, it can have an effect on file mode and it can also need to clear SGID if. - None of caller's group/supplementary groups match file owner group. AND - Caller is not priviliged (No CAP_FSETID). As of now fuser server is responsible for changing the file mode as well. But it does not know whether to clear SGID or not. So add a flag FUSE_SETXATTR_ACL_KILL_SGID and send this info with SETXATTR to let file server know that sgid needs to be cleared as well. Reported-by: Luis Henriques Signed-off-by: Vivek Goyal Signed-off-by: Miklos Szeredi --- include/uapi/linux/fuse.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/uapi/linux/fuse.h') diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 390f7b4c889d..271ae90a9bb7 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -180,6 +180,7 @@ * - add FUSE_HANDLE_KILLPRIV_V2, FUSE_WRITE_KILL_SUIDGID, FATTR_KILL_SUIDGID * - add FUSE_OPEN_KILL_SUIDGID * - extend fuse_setxattr_in, add FUSE_SETXATTR_EXT + * - add FUSE_SETXATTR_ACL_KILL_SGID */ #ifndef _LINUX_FUSE_H @@ -454,6 +455,12 @@ struct fuse_file_lock { */ #define FUSE_OPEN_KILL_SUIDGID (1 << 0) +/** + * setxattr flags + * FUSE_SETXATTR_ACL_KILL_SGID: Clear SGID when system.posix_acl_access is set + */ +#define FUSE_SETXATTR_ACL_KILL_SGID (1 << 0) + enum fuse_opcode { FUSE_LOOKUP = 1, FUSE_FORGET = 2, /* no reply */ -- cgit v1.2.3