From dc50eab76b709d68175a358d6e23a5a3890764d3 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 18 May 2024 19:39:57 +0200 Subject: Merging upstream version 6.7.7. Signed-off-by: Daniel Baumann --- fs/overlayfs/super.c | 131 +++++++++++++++++++++------------------------------ 1 file changed, 55 insertions(+), 76 deletions(-) (limited to 'fs/overlayfs/super.c') diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index c71d185980..36543e9ffd 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -34,14 +34,22 @@ static struct dentry *ovl_d_real(struct dentry *dentry, struct dentry *real = NULL, *lower; int err; - /* It's an overlay file */ + /* + * vfs is only expected to call d_real() with NULL from d_real_inode() + * and with overlay inode from file_dentry() on an overlay file. + * + * TODO: remove @inode argument from d_real() API, remove code in this + * function that deals with non-NULL @inode and remove d_real() call + * from file_dentry(). + */ if (inode && d_inode(dentry) == inode) return dentry; + else if (inode) + goto bug; if (!d_is_reg(dentry)) { - if (!inode || inode == d_inode(dentry)) - return dentry; - goto bug; + /* d_real_inode() is only relevant for regular files */ + return dentry; } real = ovl_dentry_upper(dentry); @@ -437,68 +445,6 @@ static bool ovl_workdir_ok(struct dentry *workdir, struct dentry *upperdir) return ok; } -static int ovl_own_xattr_get(const struct xattr_handler *handler, - struct dentry *dentry, struct inode *inode, - const char *name, void *buffer, size_t size) -{ - return -EOPNOTSUPP; -} - -static int ovl_own_xattr_set(const struct xattr_handler *handler, - struct mnt_idmap *idmap, - struct dentry *dentry, struct inode *inode, - const char *name, const void *value, - size_t size, int flags) -{ - return -EOPNOTSUPP; -} - -static int ovl_other_xattr_get(const struct xattr_handler *handler, - struct dentry *dentry, struct inode *inode, - const char *name, void *buffer, size_t size) -{ - return ovl_xattr_get(dentry, inode, name, buffer, size); -} - -static int ovl_other_xattr_set(const struct xattr_handler *handler, - struct mnt_idmap *idmap, - struct dentry *dentry, struct inode *inode, - const char *name, const void *value, - size_t size, int flags) -{ - return ovl_xattr_set(dentry, inode, name, value, size, flags); -} - -static const struct xattr_handler ovl_own_trusted_xattr_handler = { - .prefix = OVL_XATTR_TRUSTED_PREFIX, - .get = ovl_own_xattr_get, - .set = ovl_own_xattr_set, -}; - -static const struct xattr_handler ovl_own_user_xattr_handler = { - .prefix = OVL_XATTR_USER_PREFIX, - .get = ovl_own_xattr_get, - .set = ovl_own_xattr_set, -}; - -static const struct xattr_handler ovl_other_xattr_handler = { - .prefix = "", /* catch all */ - .get = ovl_other_xattr_get, - .set = ovl_other_xattr_set, -}; - -static const struct xattr_handler *ovl_trusted_xattr_handlers[] = { - &ovl_own_trusted_xattr_handler, - &ovl_other_xattr_handler, - NULL -}; - -static const struct xattr_handler *ovl_user_xattr_handlers[] = { - &ovl_own_user_xattr_handler, - &ovl_other_xattr_handler, - NULL -}; - static int ovl_setup_trap(struct super_block *sb, struct dentry *dir, struct inode **ptrap, const char *name) { @@ -639,7 +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) @@ -879,15 +825,20 @@ static int ovl_get_indexdir(struct super_block *sb, struct ovl_fs *ofs, { struct vfsmount *mnt = ovl_upper_mnt(ofs); struct dentry *indexdir; + struct dentry *origin = ovl_lowerstack(oe)->dentry; + const struct ovl_fh *fh; int err; + fh = ovl_get_origin_fh(ofs, origin); + if (IS_ERR(fh)) + return PTR_ERR(fh); + err = mnt_want_write(mnt); if (err) - return err; + goto out_free_fh; /* Verify lower root is upper root origin */ - err = ovl_verify_origin(ofs, upperpath->dentry, - ovl_lowerstack(oe)->dentry, true); + err = ovl_verify_origin_fh(ofs, upperpath->dentry, fh, true); if (err) { pr_err("failed to verify upper root origin\n"); goto out; @@ -919,9 +870,10 @@ static int ovl_get_indexdir(struct super_block *sb, struct ovl_fs *ofs, * directory entries. */ if (ovl_check_origin_xattr(ofs, ofs->indexdir)) { - err = ovl_verify_set_fh(ofs, ofs->indexdir, - OVL_XATTR_ORIGIN, - upperpath->dentry, true, false); + err = ovl_verify_origin_xattr(ofs, ofs->indexdir, + OVL_XATTR_ORIGIN, + upperpath->dentry, true, + false); if (err) pr_err("failed to verify index dir 'origin' xattr\n"); } @@ -939,6 +891,8 @@ static int ovl_get_indexdir(struct super_block *sb, struct ovl_fs *ofs, out: mnt_drop_write(mnt); +out_free_fh: + kfree(fh); return err; } @@ -1296,6 +1250,7 @@ static struct dentry *ovl_get_root(struct super_block *sb, struct ovl_entry *oe) { struct dentry *root; + struct ovl_fs *ofs = OVL_FS(sb); struct ovl_path *lowerpath = ovl_lowerstack(oe); unsigned long ino = d_inode(lowerpath->dentry)->i_ino; int fsid = lowerpath->layer->fsid; @@ -1317,6 +1272,20 @@ static struct dentry *ovl_get_root(struct super_block *sb, ovl_set_flag(OVL_IMPURE, d_inode(root)); } + /* Look for xwhiteouts marker except in the lowermost layer */ + for (int i = 0; i < ovl_numlower(oe) - 1; i++, lowerpath++) { + struct path path = { + .mnt = lowerpath->layer->mnt, + .dentry = lowerpath->dentry, + }; + + /* overlay.opaque=x means xwhiteouts directory */ + if (ovl_get_opaquedir_val(ofs, &path) == 'x') { + ovl_layer_set_xwhiteouts(ofs, lowerpath->layer); + ovl_dentry_set_xwhiteouts(root); + } + } + /* Root is always merge -> can have whiteouts */ ovl_set_flag(OVL_WHITEOUTS, d_inode(root)); ovl_dentry_set_flag(OVL_E_CONNECTED, root); @@ -1374,8 +1343,11 @@ int ovl_fill_super(struct super_block *sb, struct fs_context *fc) ofs->layers = layers; /* * Layer 0 is reserved for upper even if there's no upper. - * For consistency, config.lowerdirs[0] is NULL. + * config.lowerdirs[0] is used for storing the user provided colon + * separated lowerdir string. */ + ofs->config.lowerdirs[0] = ctx->lowerdir_all; + ctx->lowerdir_all = NULL; ofs->numlayer = 1; sb->s_stack_depth = 0; @@ -1485,11 +1457,18 @@ int ovl_fill_super(struct super_block *sb, struct fs_context *fc) cap_lower(cred->cap_effective, CAP_SYS_RESOURCE); sb->s_magic = OVERLAYFS_SUPER_MAGIC; - sb->s_xattr = ofs->config.userxattr ? ovl_user_xattr_handlers : - ovl_trusted_xattr_handlers; + sb->s_xattr = ovl_xattr_handlers(ofs); sb->s_fs_info = ofs; +#ifdef CONFIG_FS_POSIX_ACL sb->s_flags |= SB_POSIXACL; +#endif sb->s_iflags |= SB_I_SKIP_SYNC; + /* + * Ensure that umask handling is done by the filesystems used + * for the the upper layer instead of overlayfs as that would + * lead to unexpected results. + */ + sb->s_iflags |= SB_I_NOUMASK; err = -ENOMEM; root_dentry = ovl_get_root(sb, ctx->upper.dentry, oe); -- cgit v1.2.3