From: Christoph Hellwig hch@lst.de
mainline inclusion from mainline-v5.15-rc1 commit d07f132a225c013e59aa77f514ad9211ecab82ee category: bugfix bugzilla: 187567, https://gitee.com/openeuler/kernel/issues/I5PK1G CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/fs...
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This makes it more clear what gets added to the dcache and prepares for an additional locking fix.
Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- fs/configfs/dir.c | 73 ++++++++++++++++------------------------------- 1 file changed, 24 insertions(+), 49 deletions(-)
diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c index 59c5a1519386..31749d06bde2 100644 --- a/fs/configfs/dir.c +++ b/fs/configfs/dir.c @@ -55,7 +55,7 @@ static void configfs_d_iput(struct dentry * dentry, /* * Set sd->s_dentry to null only when this dentry is the one * that is going to be killed. Otherwise configfs_d_iput may - * run just after configfs_attach_attr and set sd->s_dentry to + * run just after configfs_lookup and set sd->s_dentry to * NULL even it's still in use. */ if (sd->s_dentry == dentry) @@ -426,44 +426,13 @@ static void configfs_remove_dir(struct config_item * item) dput(dentry); }
- -/* attaches attribute's configfs_dirent to the dentry corresponding to the - * attribute file - */ -static int configfs_attach_attr(struct configfs_dirent * sd, struct dentry * dentry) -{ - struct configfs_attribute * attr = sd->s_element; - struct inode *inode; - - spin_lock(&configfs_dirent_lock); - dentry->d_fsdata = configfs_get(sd); - sd->s_dentry = dentry; - spin_unlock(&configfs_dirent_lock); - - inode = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) | S_IFREG); - if (IS_ERR(inode)) { - configfs_put(sd); - return PTR_ERR(inode); - } - if (sd->s_type & CONFIGFS_ITEM_BIN_ATTR) { - inode->i_size = 0; - inode->i_fop = &configfs_bin_file_operations; - } else { - inode->i_size = PAGE_SIZE; - inode->i_fop = &configfs_file_operations; - } - d_add(dentry, inode); - return 0; -} - static struct dentry * configfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { struct configfs_dirent * parent_sd = dentry->d_parent->d_fsdata; struct configfs_dirent * sd; - int found = 0; - int err; + struct inode *inode = NULL;
if (dentry->d_name.len > NAME_MAX) return ERR_PTR(-ENAMETOOLONG); @@ -480,28 +449,34 @@ static struct dentry * configfs_lookup(struct inode *dir, return ERR_PTR(-ENOENT);
list_for_each_entry(sd, &parent_sd->s_children, s_sibling) { - if (sd->s_type & CONFIGFS_NOT_PINNED) { - const unsigned char * name = configfs_get_name(sd); + if ((sd->s_type & CONFIGFS_NOT_PINNED) && + !strcmp(configfs_get_name(sd), dentry->d_name.name)) { + struct configfs_attribute *attr = sd->s_element; + umode_t mode = (attr->ca_mode & S_IALLUGO) | S_IFREG;
- if (strcmp(name, dentry->d_name.name)) - continue; + spin_lock(&configfs_dirent_lock); + dentry->d_fsdata = configfs_get(sd); + sd->s_dentry = dentry; + spin_unlock(&configfs_dirent_lock);
- found = 1; - err = configfs_attach_attr(sd, dentry); + inode = configfs_create(dentry, mode); + if (IS_ERR(inode)) { + configfs_put(sd); + return ERR_CAST(inode); + } + if (sd->s_type & CONFIGFS_ITEM_BIN_ATTR) { + inode->i_size = 0; + inode->i_fop = &configfs_bin_file_operations; + } else { + inode->i_size = PAGE_SIZE; + inode->i_fop = &configfs_file_operations; + } break; } }
- if (!found) { - /* - * If it doesn't exist and it isn't a NOT_PINNED item, - * it must be negative. - */ - d_add(dentry, NULL); - return NULL; - } - - return ERR_PTR(err); + d_add(dentry, inode); + return NULL; }
/*