From b9849f286b81ffb65208dd5f4bf6162efe1eca97 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 3 Dec 2015 13:54:33 +0000 Subject: [PATCH] kernel: add overlayfs stacking fix from upstream Overlayfs stacking was broken in 4.1.12 but now fixed in upstream branch. Stacking allows experimenting with configurations without the need to reset a device to factory config. Signed-off-by: Roman Yeryomin Signed-off-by: Felix Fietkau SVN-Revision: 47714 --- .../040-fs-overlay-fix-stacking.patch | 33 +++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 target/linux/generic/patches-4.1/040-fs-overlay-fix-stacking.patch diff --git a/target/linux/generic/patches-4.1/040-fs-overlay-fix-stacking.patch b/target/linux/generic/patches-4.1/040-fs-overlay-fix-stacking.patch new file mode 100644 index 0000000000..b3bb5c7e8a --- /dev/null +++ b/target/linux/generic/patches-4.1/040-fs-overlay-fix-stacking.patch @@ -0,0 +1,33 @@ +From 1c8a47df36d72ace8cf78eb6c228aa0f8027d3c2 Mon Sep 17 00:00:00 2001 +From: Miklos Szeredi +Date: Mon, 12 Oct 2015 15:56:20 +0200 +Subject: ovl: fix open in stacked overlay + +If two overlayfs filesystems are stacked on top of each other, then we need +recursion in ovl_d_select_inode(). + +I guess d_backing_inode() is supposed to do that. But currently it doesn't +and that functionality is open coded in vfs_open(). This is now copied +into ovl_d_select_inode() to fix this regression. + +Reported-by: Alban Crequy +Signed-off-by: Miklos Szeredi +Fixes: 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay...") +Cc: David Howells +Cc: # v4.2+ +--- + fs/overlayfs/inode.c | 3 +++ + 1 file changed, 3 insertions(+) + +--- a/fs/overlayfs/inode.c ++++ b/fs/overlayfs/inode.c +@@ -362,6 +362,9 @@ struct inode *ovl_d_select_inode(struct + ovl_path_upper(dentry, &realpath); + } + ++ if (realpath.dentry->d_flags & DCACHE_OP_SELECT_INODE) ++ return realpath.dentry->d_op->d_select_inode(realpath.dentry, file_flags); ++ + return d_backing_inode(realpath.dentry); + } + -- 2.30.2