From f4439de118283159ff165e52036134a278ebf990 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Tue, 4 Jul 2017 22:04:06 +0300 Subject: [PATCH] ovl: mark parent impure and restore timestamp on ovl_link_up() Signed-off-by: Amir Goldstein --- fs/overlayfs/copy_up.c | 57 +++++++++++++++++++++++++++++--------------------- 1 file changed, 33 insertions(+), 24 deletions(-) diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index f193976..acb6f97 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -316,48 +316,57 @@ static int ovl_set_origin(struct dentry *dentry, struct dentry *lower, return err; } -static int ovl_link_up(struct dentry *parent, struct dentry *dentry) +struct ovl_copy_up_ctx { + struct dentry *parent; + struct dentry *dentry; + struct path lowerpath; + struct kstat stat; + struct kstat pstat; + const char *link; + struct dentry *destdir; + struct qstr destname; + struct dentry *workdir; + bool tmpfile; + bool origin; +}; + +static int ovl_link_up(struct ovl_copy_up_ctx *c) { int err; struct dentry *upper; - struct dentry *upperdir = ovl_dentry_upper(parent); + struct dentry *upperdir = ovl_dentry_upper(c->parent); struct inode *udir = d_inode(upperdir); - err = ovl_set_nlink_lower(dentry); + /* Mark parent "impure" because it may now contain non-pure upper */ + err = ovl_set_impure(c->parent, upperdir); + if (err) + return err; + + err = ovl_set_nlink_lower(c->dentry); if (err) return err; inode_lock_nested(udir, I_MUTEX_PARENT); - upper = lookup_one_len(dentry->d_name.name, upperdir, - dentry->d_name.len); + upper = lookup_one_len(c->dentry->d_name.name, upperdir, + c->dentry->d_name.len); err = PTR_ERR(upper); if (!IS_ERR(upper)) { - err = ovl_do_link(ovl_dentry_upper(dentry), udir, upper, true); + err = ovl_do_link(ovl_dentry_upper(c->dentry), udir, upper, + true); dput(upper); - if (!err) - ovl_dentry_set_upper_alias(dentry); + if (!err) { + /* Restore timestamps on parent (best effort) */ + ovl_set_timestamps(upperdir, &c->pstat); + ovl_dentry_set_upper_alias(c->dentry); + } } inode_unlock(udir); - ovl_set_nlink_upper(dentry); + ovl_set_nlink_upper(c->dentry); return err; } -struct ovl_copy_up_ctx { - struct dentry *parent; - struct dentry *dentry; - struct path lowerpath; - struct kstat stat; - struct kstat pstat; - const char *link; - struct dentry *destdir; - struct qstr destname; - struct dentry *workdir; - bool tmpfile; - bool origin; -}; - static int ovl_install_temp(struct ovl_copy_up_ctx *c, struct dentry *temp, struct dentry **newdentry) { @@ -629,7 +638,7 @@ static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, if (!ovl_dentry_upper(dentry)) err = ovl_do_copy_up(&ctx); if (!err && !ovl_dentry_has_upper_alias(dentry)) - err = ovl_link_up(parent, dentry); + err = ovl_link_up(&ctx); ovl_copy_up_end(dentry); } do_delayed_call(&done); -- 2.7.4