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Diffstat (limited to 'Documentation/filesystems/overlayfs.txt')
| -rw-r--r-- | Documentation/filesystems/overlayfs.txt | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt index 8caa60734647..e6a5f4912b6d 100644 --- a/Documentation/filesystems/overlayfs.txt +++ b/Documentation/filesystems/overlayfs.txt @@ -156,6 +156,40 @@ handle it in two different ways: root of the overlay. Finally the directory is moved to the new location. +There are several ways to tune the "redirect_dir" feature. + +Kernel config options: + +- OVERLAY_FS_REDIRECT_DIR: + If this is enabled, then redirect_dir is turned on by default. +- OVERLAY_FS_REDIRECT_ALWAYS_FOLLOW: + If this is enabled, then redirects are always followed by default. Enabling + this results in a less secure configuration. Enable this option only when + worried about backward compatibility with kernels that have the redirect_dir + feature and follow redirects even if turned off. + +Module options (can also be changed through /sys/module/overlay/parameters/*): + +- "redirect_dir=BOOL": + See OVERLAY_FS_REDIRECT_DIR kernel config option above. +- "redirect_always_follow=BOOL": + See OVERLAY_FS_REDIRECT_ALWAYS_FOLLOW kernel config option above. +- "redirect_max=NUM": + The maximum number of bytes in an absolute redirect (default is 256). + +Mount options: + +- "redirect_dir=on": + Redirects are enabled. +- "redirect_dir=follow": + Redirects are not created, but followed. +- "redirect_dir=off": + Redirects are not created and only followed if "redirect_always_follow" + feature is enabled in the kernel/module config. +- "redirect_dir=nofollow": + Redirects are not created and not followed (equivalent to "redirect_dir=off" + if "redirect_always_follow" feature is not enabled). + Non-directories --------------- |