Merge pull request #323 from giuseppe/add-flag-to-disable-acl

main: add a mount flag to disable ACLs

fuse-overlayfs.1

@@ -1,55 +1,55 @@
 .nh
-.TH fuse\-overlayfs 1 "User Commands"
+.TH fuse-overlayfs 1 "User Commands"
 
 .SH NAME
 .PP
-fuse\-overlayfs \- overlayfs FUSE implementation
+fuse-overlayfs - overlayfs FUSE implementation
 
 
 .SH SYNOPSIS
 .PP
 mounting
-    fuse\-overlayfs [\-f] [\-\-debug] [\-o OPTS] MOUNT\_TARGET
+    fuse-overlayfs [-f] [--debug] [-o OPTS] MOUNT_TARGET
 
 .PP
 unmounting
-    fusermount \-u mountpoint
+    fusermount -u mountpoint
 
 
 .SH DESCRIPTION
 .PP
-fuse\-overlayfs provides an overlayfs FUSE implementation so that it
+fuse-overlayfs provides an overlayfs FUSE implementation so that it
 can be used since Linux 4.18 by unprivileged users in an user
 namespace.
 
 
 .SH OPTIONS
 .PP
-\fB\-\-debug\fP
+\fB--debug\fP
 Enable debugging mode, can be very noisy.
 
 .PP
-\fB\-o lowerdir=low1[:low2...]\fP
+\fB-o lowerdir=low1[:low2...]\fP
 A list of directories separated by \fB\fC:\fR\&.  Their content is merged.
 
 .PP
-\fB\-o upperdir=upperdir\fP
+\fB-o upperdir=upperdir\fP
 A directory merged on top of all the lowerdirs where all the changes
 done to the file system will be written.
 
 .PP
-\fB\-o workdir=workdir\fP
-A directory used internally by fuse\-overlays, must be on the same file
+\fB-o workdir=workdir\fP
+A directory used internally by fuse-overlays, must be on the same file
 system as the upper dir.
 
 .PP
-\fB\-o uidmapping=UID:MAPPED\-UID:LEN[,UID2:MAPPED\-UID2:LEN2]\fP
-\fB\-o gidmapping=GID:MAPPED\-GID:LEN[,GID2:MAPPED\-GID2:LEN2]\fP
-Specifies the dynamic UID/GID mapping used by fuse\-overlayfs when
+\fB-o uidmapping=UID:MAPPED-UID:LEN[,UID2:MAPPED-UID2:LEN2]\fP
+\fB-o gidmapping=GID:MAPPED-GID:LEN[,GID2:MAPPED-GID2:LEN2]\fP
+Specifies the dynamic UID/GID mapping used by fuse-overlayfs when
 reading/writing files to the system.
 
 .PP
-The fuse\-overlayfs dynamic mapping is an alternative and cheaper way
+The fuse-overlayfs dynamic mapping is an alternative and cheaper way
 to chown'ing the files on the host to accommodate the user namespace
 settings.
 
@@ -62,21 +62,21 @@ without requiring to chown the files.
 For example, given on the host two files like:
 
 .PP
-$ stat \-c %u:%g lower/a lower/b
+$ stat -c %u:%g lower/a lower/b
 0:0
 1:1
 
 .PP
 When we run in a user namespace with the following configuration:
-$ cat /proc/self/uid\_map
+$ cat /proc/self/uid_map
          0       1000          1
          1     110000      65536
 
 .PP
 We would see:
 
 .PP
-$ stat \-c %u:%g merged/a merged/b
+$ stat -c %u:%g merged/a merged/b
 65534:65534
 65534:65534
 
@@ -86,48 +86,52 @@ user namespace.  This happens because both users 0:0 and 1:1 are not
 mapped.
 
 .PP
-In the above example, if we mount the fuse\-overlayfs file system using:
-\fB\fC\-ouidmapping=0:1000:1:1:110000:65536,gidmapping=0:1000:1:1:110000:65536\fR,
+In the above example, if we mount the fuse-overlayfs file system using:
+\fB\fC-ouidmapping=0:1000:1:1:110000:65536,gidmapping=0:1000:1:1:110000:65536\fR,
 which is the namespace configuration specified on a single line, we'd
 see from the same user namespace:
 
 .PP
-$ stat \-c %u:%g merged/a merged/b
+$ stat -c %u:%g merged/a merged/b
 0:0
 1:1
 
 .PP
 Those are the same IDs visible from outside the user namespace.
 
 .PP
-\fB\-o squash\_to\_root\fP
+\fB-o squash_to_root\fP
 Every file and directory is owned by the root user (0:0).
 
 .PP
-\fB\-o squash\_to\_uid=uid\fP
-\fB\-o squash\_to\_gid=gid\fP
+\fB-o squash_to_uid=uid\fP
+\fB-o squash_to_gid=gid\fP
 Every file and directory is owned by the specified uid or gid.
 
 .PP
-It has higher precedence over \fBsquash\_to\_root\fP\&.
+It has higher precedence over \fBsquash_to_root\fP\&.
 
 .PP
-\fB\-o static\_nlink\fP
-Set st\_nlink to the static value 1 for all directories.
+\fB-o static_nlink\fP
+Set st_nlink to the static value 1 for all directories.
 
 .PP
 This can be useful for higher latency file systems such as NFS, where
 counting the number of hard links for a directory with many files can
 be a slow operation. With this option enabled, the number of hard
 links reported when running stat for any directory is 1.
 
+.PP
+\fB-o noacl\fP
+Disable ACL support in the FUSE file system.
+
 
 .SH SEE ALSO
 .PP
-\fBfuse\fP(8), \fBmount\fP(8), \fBuser\_namespaces\fP(7)
+\fBfuse\fP(8), \fBmount\fP(8), \fBuser_namespaces\fP(7)
 
 
 .SH AVAILABILITY
 .PP
-The fuse\-overlayfs command is available from
-\fBhttps://github.com/containers/fuse\-overlayfs\fP under GNU GENERAL PUBLIC LICENSE Version 3 or later.
+The fuse-overlayfs command is available from
+\fBhttps://github.com/containers/fuse-overlayfs\fP under GNU GENERAL PUBLIC LICENSE Version 3 or later.

fuse-overlayfs.1.md

@@ -97,6 +97,9 @@ counting the number of hard links for a directory with many files can
 be a slow operation. With this option enabled, the number of hard
 links reported when running stat for any directory is 1.
 
+**-o noacl**
+Disable ACL support in the FUSE file system.
+
 # SEE ALSO
 
 **fuse**(8), **mount**(8), **user_namespaces**(7)

fuse-overlayfs.h

@@ -92,6 +92,7 @@ struct ovl_data
   double timeout;
   int threaded;
   int fsync;
+  int noacl;
   int fast_ino_check;
   int writeback;
   int disable_xattrs;

main.c

@@ -227,6 +227,8 @@ static const struct fuse_opt ovl_opts[] = {
    offsetof (struct ovl_data, static_nlink), 1},
   {"volatile",  /* native overlay supports "volatile" to mean fsync=0.  */
    offsetof (struct ovl_data, fsync), 0},
+  {"noacl",
+   offsetof (struct ovl_data, noacl), 1},
   FUSE_OPT_END
 };
 
@@ -427,7 +429,7 @@ ovl_init (void *userdata, struct fuse_conn_info *conn)
   if ((conn->capable & FUSE_CAP_WRITEBACK_CACHE) == 0)
     lo->writeback = 0;
 
-  if (conn->capable & FUSE_CAP_POSIX_ACL)
+  if ((lo->noacl == 0) && (conn->capable & FUSE_CAP_POSIX_ACL))
     conn->want |= FUSE_CAP_POSIX_ACL;
 
   conn->want |= FUSE_CAP_DONT_MASK | FUSE_CAP_SPLICE_READ | FUSE_CAP_SPLICE_WRITE | FUSE_CAP_SPLICE_MOVE;
@@ -5515,6 +5517,7 @@ main (int argc, char *argv[])
                         .redirect_dir = NULL,
                         .mountpoint = NULL,
                         .fsync = 1,
+                        .noacl = 0,
                         .squash_to_uid = -1,
                         .squash_to_gid = -1,
                         .static_nlink = 0,