[PATCH] Add NOSYMFOLLOW flags to mount(2) and statfs(2)

[Ross Zwisler <zwisler@chromium.org>]

These flags should first appear in Linux kernel version v5.10.

Signed-off-by: Ross Zwisler <zwisler@google.com>
---
The nosymfollow kernel code has been merged into Al Viro's tree and
should be part of the v5.10 merge window.
https://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git/commit/?h=work.misc&id=dab741e0e02bd3c4f5e2e97be74b39df2523fc6e
---
 man2/mount.2  | 10 ++++++++++
 man2/statfs.2 |  4 ++++
 2 files changed, 14 insertions(+)

diff --git a/man2/mount.2 b/man2/mount.2
index f565ee578..039e4b83b 100644
--- a/man2/mount.2
+++ b/man2/mount.2
@@ -280,6 +280,16 @@ the
 flag to
 .BR open (2)
 was specified for all file opens to this filesystem).
+.TP
+.B MS_NOSYMFOLLOW
+Do not follow symlinks when resolving paths.  Symlinks can still be created,
+and
+.BR readlink (1),
+.BR readlink (2),
+.BR realpath (1)
+and
+.BR realpath (3)
+all still work properly.
 .PP
 From Linux 2.4 onward, some of the above flags are
 settable on a per-mount basis,
diff --git a/man2/statfs.2 b/man2/statfs.2
index 0fc537c14..d5edf2a50 100644
--- a/man2/statfs.2
+++ b/man2/statfs.2
@@ -206,6 +206,10 @@ Writes are synched to the filesystem immediately (see the description of
 .B O_SYNC
 in
 .BR open (2)).
+.TP
+.B ST_NOSYMFOLLOW
+Symlinks are not followed when resolving paths; see
+.BR mount (2).
 .PP
 Nobody knows what
 .I f_fsid
-- 
2.28.0.526.ge36021eeef-goog