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-rw-r--r--fs/overlayfs/dir.c4
-rw-r--r--fs/overlayfs/namei.c15
-rw-r--r--fs/overlayfs/overlayfs.h15
-rw-r--r--fs/overlayfs/readdir.c27
-rw-r--r--fs/overlayfs/super.c2
-rw-r--r--fs/overlayfs/util.c40
6 files changed, 88 insertions, 15 deletions
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 768120c20f85..aab3f5d93556 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -477,7 +477,7 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
goto out_unlock;
err = -ESTALE;
- if (d_is_negative(upper) || !IS_WHITEOUT(d_inode(upper)))
+ if (d_is_negative(upper) || !ovl_upper_is_whiteout(ofs, upper))
goto out_dput;
newdentry = ovl_create_temp(ofs, workdir, cattr);
@@ -1211,7 +1211,7 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
}
} else {
if (!d_is_negative(newdentry)) {
- if (!new_opaque || !ovl_is_whiteout(newdentry))
+ if (!new_opaque || !ovl_upper_is_whiteout(ofs, newdentry))
goto out_dput;
} else {
if (flags & RENAME_EXCHANGE)
diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index f10ac4ae35f0..03bc8d5dfa31 100644
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -251,7 +251,10 @@ static int ovl_lookup_single(struct dentry *base, struct ovl_lookup_data *d,
err = -EREMOTE;
goto out_err;
}
- if (ovl_is_whiteout(this)) {
+
+ path.dentry = this;
+ path.mnt = d->mnt;
+ if (ovl_path_is_whiteout(OVL_FS(d->sb), &path)) {
d->stop = d->opaque = true;
goto put_and_out;
}
@@ -264,8 +267,6 @@ static int ovl_lookup_single(struct dentry *base, struct ovl_lookup_data *d,
goto put_and_out;
}
- path.dentry = this;
- path.mnt = d->mnt;
if (!d_can_lookup(this)) {
if (d->is_dir || !last_element) {
d->stop = true;
@@ -438,7 +439,7 @@ int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected,
else if (IS_ERR(origin))
return PTR_ERR(origin);
- if (upperdentry && !ovl_is_whiteout(upperdentry) &&
+ if (upperdentry && !ovl_upper_is_whiteout(ofs, upperdentry) &&
inode_wrong_type(d_inode(upperdentry), d_inode(origin)->i_mode))
goto invalid;
@@ -1402,7 +1403,11 @@ bool ovl_lower_positive(struct dentry *dentry)
break;
}
} else {
- positive = !ovl_is_whiteout(this);
+ struct path path = {
+ .dentry = this,
+ .mnt = parentpath->layer->mnt,
+ };
+ positive = !ovl_path_is_whiteout(OVL_FS(dentry->d_sb), &path);
done = true;
dput(this);
}
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 393c6ba9bffa..ca88b2636a57 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -49,6 +49,8 @@ enum ovl_xattr {
OVL_XATTR_UUID,
OVL_XATTR_METACOPY,
OVL_XATTR_PROTATTR,
+ OVL_XATTR_XWHITEOUT,
+ OVL_XATTR_XWHITEOUTS,
};
enum ovl_inode_flag {
@@ -473,6 +475,7 @@ void ovl_inode_update(struct inode *inode, struct dentry *upperdentry);
void ovl_dir_modified(struct dentry *dentry, bool impurity);
u64 ovl_inode_version_get(struct inode *inode);
bool ovl_is_whiteout(struct dentry *dentry);
+bool ovl_path_is_whiteout(struct ovl_fs *ofs, const struct path *path);
struct file *ovl_path_open(const struct path *path, int flags);
int ovl_copy_up_start(struct dentry *dentry, int flags);
void ovl_copy_up_end(struct dentry *dentry);
@@ -480,9 +483,21 @@ bool ovl_already_copied_up(struct dentry *dentry, int flags);
bool ovl_path_check_dir_xattr(struct ovl_fs *ofs, const struct path *path,
enum ovl_xattr ox);
bool ovl_path_check_origin_xattr(struct ovl_fs *ofs, const struct path *path);
+bool ovl_path_check_xwhiteout_xattr(struct ovl_fs *ofs, const struct path *path);
+bool ovl_path_check_xwhiteouts_xattr(struct ovl_fs *ofs, const struct path *path);
bool ovl_init_uuid_xattr(struct super_block *sb, struct ovl_fs *ofs,
const struct path *upperpath);
+static inline bool ovl_upper_is_whiteout(struct ovl_fs *ofs,
+ struct dentry *upperdentry)
+{
+ struct path upperpath = {
+ .dentry = upperdentry,
+ .mnt = ovl_upper_mnt(ofs),
+ };
+ return ovl_path_is_whiteout(ofs, &upperpath);
+}
+
static inline bool ovl_check_origin_xattr(struct ovl_fs *ofs,
struct dentry *upperdentry)
{
diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index de39e067ae65..a490fc47c3e7 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -25,6 +25,7 @@ struct ovl_cache_entry {
struct ovl_cache_entry *next_maybe_whiteout;
bool is_upper;
bool is_whiteout;
+ bool check_xwhiteout;
char name[];
};
@@ -47,6 +48,7 @@ struct ovl_readdir_data {
int err;
bool is_upper;
bool d_type_supported;
+ bool in_xwhiteouts_dir;
};
struct ovl_dir_file {
@@ -162,6 +164,8 @@ static struct ovl_cache_entry *ovl_cache_entry_new(struct ovl_readdir_data *rdd,
p->ino = 0;
p->is_upper = rdd->is_upper;
p->is_whiteout = false;
+ /* Defer check for overlay.whiteout to ovl_iterate() */
+ p->check_xwhiteout = rdd->in_xwhiteouts_dir && d_type == DT_REG;
if (d_type == DT_CHR) {
p->next_maybe_whiteout = rdd->first_maybe_whiteout;
@@ -301,6 +305,8 @@ static inline int ovl_dir_read(const struct path *realpath,
if (IS_ERR(realfile))
return PTR_ERR(realfile);
+ rdd->in_xwhiteouts_dir = rdd->dentry &&
+ ovl_path_check_xwhiteouts_xattr(OVL_FS(rdd->dentry->d_sb), realpath);
rdd->first_maybe_whiteout = NULL;
rdd->ctx.pos = 0;
do {
@@ -447,7 +453,7 @@ static u64 ovl_remap_lower_ino(u64 ino, int xinobits, int fsid,
}
/*
- * Set d_ino for upper entries. Non-upper entries should always report
+ * Set d_ino for upper entries if needed. Non-upper entries should always report
* the uppermost real inode ino and should not call this function.
*
* When not all layer are on same fs, report real ino also for upper.
@@ -455,8 +461,11 @@ static u64 ovl_remap_lower_ino(u64 ino, int xinobits, int fsid,
* When all layers are on the same fs, and upper has a reference to
* copy up origin, call vfs_getattr() on the overlay entry to make
* sure that d_ino will be consistent with st_ino from stat(2).
+ *
+ * Also checks the overlay.whiteout xattr by doing a full lookup which will return
+ * negative in this case.
*/
-static int ovl_cache_update_ino(const struct path *path, struct ovl_cache_entry *p)
+static int ovl_cache_update(const struct path *path, struct ovl_cache_entry *p, bool update_ino)
{
struct dentry *dir = path->dentry;
@@ -467,7 +476,7 @@ static int ovl_cache_update_ino(const struct path *path, struct ovl_cache_entry
int xinobits = ovl_xino_bits(ofs);
int err = 0;
- if (!ovl_same_dev(ofs))
+ if (!ovl_same_dev(ofs) && !p->check_xwhiteout)
goto out;
if (p->name[0] == '.') {
@@ -481,6 +490,7 @@ static int ovl_cache_update_ino(const struct path *path, struct ovl_cache_entry
goto get;
}
}
+ /* This checks also for xwhiteouts */
this = lookup_one(mnt_idmap(path->mnt), p->name, dir, p->len);
if (IS_ERR_OR_NULL(this) || !this->d_inode) {
/* Mark a stale entry */
@@ -494,6 +504,9 @@ static int ovl_cache_update_ino(const struct path *path, struct ovl_cache_entry
}
get:
+ if (!ovl_same_dev(ofs) || !update_ino)
+ goto out;
+
type = ovl_path_type(this);
if (OVL_TYPE_ORIGIN(type)) {
struct kstat stat;
@@ -572,7 +585,7 @@ static int ovl_dir_read_impure(const struct path *path, struct list_head *list,
list_for_each_entry_safe(p, n, list, l_node) {
if (strcmp(p->name, ".") != 0 &&
strcmp(p->name, "..") != 0) {
- err = ovl_cache_update_ino(path, p);
+ err = ovl_cache_update(path, p, true);
if (err)
return err;
}
@@ -778,13 +791,13 @@ static int ovl_iterate(struct file *file, struct dir_context *ctx)
while (od->cursor != &od->cache->entries) {
p = list_entry(od->cursor, struct ovl_cache_entry, l_node);
if (!p->is_whiteout) {
- if (!p->ino) {
- err = ovl_cache_update_ino(&file->f_path, p);
+ if (!p->ino || p->check_xwhiteout) {
+ err = ovl_cache_update(&file->f_path, p, !p->ino);
if (err)
goto out;
}
}
- /* ovl_cache_update_ino() sets is_whiteout on stale entry */
+ /* ovl_cache_update() sets is_whiteout on stale entry */
if (!p->is_whiteout) {
if (!dir_emit(ctx, p->name, p->len, p->ino, p->type))
break;
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 0a42a25656fa..1a95ee237fa9 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -585,7 +585,7 @@ static int ovl_check_rename_whiteout(struct ovl_fs *ofs)
if (IS_ERR(whiteout))
goto cleanup_temp;
- err = ovl_is_whiteout(whiteout);
+ err = ovl_upper_is_whiteout(ofs, whiteout);
/* Best effort cleanup of whiteout and temp file */
if (err)
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index f8455fcb8b07..73ac47b49218 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -601,6 +601,16 @@ bool ovl_is_whiteout(struct dentry *dentry)
return inode && IS_WHITEOUT(inode);
}
+/*
+ * Use this over ovl_is_whiteout for upper and lower files, as it also
+ * handles overlay.whiteout xattr whiteout files.
+ */
+bool ovl_path_is_whiteout(struct ovl_fs *ofs, const struct path *path)
+{
+ return ovl_is_whiteout(path->dentry) ||
+ ovl_path_check_xwhiteout_xattr(ofs, path);
+}
+
struct file *ovl_path_open(const struct path *path, int flags)
{
struct inode *inode = d_inode(path->dentry);
@@ -716,6 +726,32 @@ bool ovl_path_check_origin_xattr(struct ovl_fs *ofs, const struct path *path)
return false;
}
+bool ovl_path_check_xwhiteout_xattr(struct ovl_fs *ofs, const struct path *path)
+{
+ struct dentry *dentry = path->dentry;
+ int res;
+
+ /* xattr.whiteout must be a zero size regular file */
+ if (!d_is_reg(dentry) || i_size_read(d_inode(dentry)) != 0)
+ return false;
+
+ res = ovl_path_getxattr(ofs, path, OVL_XATTR_XWHITEOUT, NULL, 0);
+ return res >= 0;
+}
+
+bool ovl_path_check_xwhiteouts_xattr(struct ovl_fs *ofs, const struct path *path)
+{
+ struct dentry *dentry = path->dentry;
+ int res;
+
+ /* xattr.whiteouts must be a directory */
+ if (!d_is_dir(dentry))
+ return false;
+
+ res = ovl_path_getxattr(ofs, path, OVL_XATTR_XWHITEOUTS, NULL, 0);
+ return res >= 0;
+}
+
/*
* Load persistent uuid from xattr into s_uuid if found, or store a new
* random generated value in s_uuid and in xattr.
@@ -800,6 +836,8 @@ bool ovl_path_check_dir_xattr(struct ovl_fs *ofs, const struct path *path,
#define OVL_XATTR_UUID_POSTFIX "uuid"
#define OVL_XATTR_METACOPY_POSTFIX "metacopy"
#define OVL_XATTR_PROTATTR_POSTFIX "protattr"
+#define OVL_XATTR_XWHITEOUT_POSTFIX "whiteout"
+#define OVL_XATTR_XWHITEOUTS_POSTFIX "whiteouts"
#define OVL_XATTR_TAB_ENTRY(x) \
[x] = { [false] = OVL_XATTR_TRUSTED_PREFIX x ## _POSTFIX, \
@@ -815,6 +853,8 @@ const char *const ovl_xattr_table[][2] = {
OVL_XATTR_TAB_ENTRY(OVL_XATTR_UUID),
OVL_XATTR_TAB_ENTRY(OVL_XATTR_METACOPY),
OVL_XATTR_TAB_ENTRY(OVL_XATTR_PROTATTR),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_XWHITEOUT),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_XWHITEOUTS),
};
int ovl_check_setxattr(struct ovl_fs *ofs, struct dentry *upperdentry,
generated by cgit (git 2.34.1) at 2024-05-28 08:18:55 +0000