lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-ID: <20200601134222.37235-1-yi.zhang@huawei.com> Date: Mon, 1 Jun 2020 21:42:22 +0800 From: "zhangyi (F)" <yi.zhang@...wei.com> To: <linux-ext4@...r.kernel.org> CC: <jack@...e.cz>, <yi.zhang@...wei.com> Subject: [PATCH] ext2: propagate errors up to ext2_find_entry()'s callers The same to commit <36de928641ee4> (ext4: propagate errors up to ext4_find_entry()'s callers') in ext4, also return error instead of NULL pointer in case of some error happens in ext2_find_entry() (e.g. -ENOMEM or -EIO). This could avoid a negative dentry cache entry installed even it failed to read directory block due to IO error. Signed-off-by: zhangyi (F) <yi.zhang@...wei.com> --- fs/ext2/dir.c | 62 +++++++++++++++++++++++++------------------------ fs/ext2/ext2.h | 3 ++- fs/ext2/namei.c | 28 ++++++++++++++++++---- 3 files changed, 58 insertions(+), 35 deletions(-) diff --git a/fs/ext2/dir.c b/fs/ext2/dir.c index 13318e255ebf..1c3ab60890b1 100644 --- a/fs/ext2/dir.c +++ b/fs/ext2/dir.c @@ -347,8 +347,7 @@ struct ext2_dir_entry_2 *ext2_find_entry (struct inode *dir, unsigned long npages = dir_pages(dir); struct page *page = NULL; struct ext2_inode_info *ei = EXT2_I(dir); - ext2_dirent * de; - int dir_has_error = 0; + ext2_dirent *de, *ret = NULL; if (npages == 0) goto out; @@ -362,25 +361,28 @@ struct ext2_dir_entry_2 *ext2_find_entry (struct inode *dir, n = start; do { char *kaddr; - page = ext2_get_page(dir, n, dir_has_error); - if (!IS_ERR(page)) { - kaddr = page_address(page); - de = (ext2_dirent *) kaddr; - kaddr += ext2_last_byte(dir, n) - reclen; - while ((char *) de <= kaddr) { - if (de->rec_len == 0) { - ext2_error(dir->i_sb, __func__, - "zero-length directory entry"); - ext2_put_page(page); - goto out; - } - if (ext2_match (namelen, name, de)) - goto found; - de = ext2_next_entry(de); + page = ext2_get_page(dir, n, 0); + if (IS_ERR(page)) { + ret = ERR_CAST(page); + goto out; + } + kaddr = page_address(page); + de = (ext2_dirent *) kaddr; + kaddr += ext2_last_byte(dir, n) - reclen; + while ((char *) de <= kaddr) { + if (de->rec_len == 0) { + ext2_error(dir->i_sb, __func__, + "zero-length directory entry"); + ext2_put_page(page); + goto out; } - ext2_put_page(page); - } else - dir_has_error = 1; + if (ext2_match(namelen, name, de)) { + ret = de; + goto found; + } + de = ext2_next_entry(de); + } + ext2_put_page(page); if (++n >= npages) n = 0; @@ -394,12 +396,12 @@ struct ext2_dir_entry_2 *ext2_find_entry (struct inode *dir, } } while (n != start); out: - return NULL; + return ret; found: *res_page = page; ei->i_dir_start_lookup = n; - return de; + return ret; } struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p) @@ -414,18 +416,18 @@ struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p) return de; } -ino_t ext2_inode_by_name(struct inode *dir, const struct qstr *child) +int ext2_inode_by_name(struct inode *dir, const struct qstr *child, ino_t *ino) { - ino_t res = 0; struct ext2_dir_entry_2 *de; struct page *page; - de = ext2_find_entry (dir, child, &page); - if (de) { - res = le32_to_cpu(de->inode); - ext2_put_page(page); - } - return res; + de = ext2_find_entry(dir, child, &page); + if (IS_ERR_OR_NULL(de)) + return PTR_ERR(de); + + *ino = le32_to_cpu(de->inode); + ext2_put_page(page); + return 0; } static int ext2_prepare_chunk(struct page *page, loff_t pos, unsigned len) diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h index 8178bd38a9d6..a321ff9bf1b4 100644 --- a/fs/ext2/ext2.h +++ b/fs/ext2/ext2.h @@ -738,7 +738,8 @@ extern void ext2_rsv_window_add(struct super_block *sb, struct ext2_reserve_wind /* dir.c */ extern int ext2_add_link (struct dentry *, struct inode *); -extern ino_t ext2_inode_by_name(struct inode *, const struct qstr *); +extern int ext2_inode_by_name(struct inode *dir, + const struct qstr *child, ino_t *ino); extern int ext2_make_empty(struct inode *, struct inode *); extern struct ext2_dir_entry_2 * ext2_find_entry (struct inode *,const struct qstr *, struct page **); extern int ext2_delete_entry (struct ext2_dir_entry_2 *, struct page *); diff --git a/fs/ext2/namei.c b/fs/ext2/namei.c index ccfbbf59e2fc..f888e2146345 100644 --- a/fs/ext2/namei.c +++ b/fs/ext2/namei.c @@ -56,12 +56,15 @@ static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode) static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags) { struct inode * inode; - ino_t ino; + ino_t ino = 0; + int res; if (dentry->d_name.len > EXT2_NAME_LEN) return ERR_PTR(-ENAMETOOLONG); - ino = ext2_inode_by_name(dir, &dentry->d_name); + res = ext2_inode_by_name(dir, &dentry->d_name, &ino); + if (res) + return ERR_PTR(res); inode = NULL; if (ino) { inode = ext2_iget(dir->i_sb, ino); @@ -78,7 +81,12 @@ static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, uns struct dentry *ext2_get_parent(struct dentry *child) { struct qstr dotdot = QSTR_INIT("..", 2); - unsigned long ino = ext2_inode_by_name(d_inode(child), &dotdot); + ino_t ino = 0; + int res; + + res = ext2_inode_by_name(d_inode(child), &dotdot, &ino); + if (res) + return ERR_PTR(res); if (!ino) return ERR_PTR(-ENOENT); return d_obtain_alias(ext2_iget(child->d_sb, ino)); @@ -277,6 +285,10 @@ static int ext2_unlink(struct inode * dir, struct dentry *dentry) goto out; de = ext2_find_entry (dir, &dentry->d_name, &page); + if (IS_ERR(de)) { + err = PTR_ERR(de); + goto out; + } if (!de) { err = -ENOENT; goto out; @@ -332,7 +344,11 @@ static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry, if (err) goto out; - old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page); + old_de = ext2_find_entry(old_dir, &old_dentry->d_name, &old_page); + if (IS_ERR(old_de)) { + err = PTR_ERR(old_de); + goto out; + } if (!old_de) { err = -ENOENT; goto out; @@ -355,6 +371,10 @@ static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry, err = -ENOENT; new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page); + if (IS_ERR(new_de)) { + err = PTR_ERR(new_de); + goto out_dir; + } if (!new_de) goto out_dir; ext2_set_link(new_dir, new_de, new_page, old_inode, 1); -- 2.21.3
Powered by blists - more mailing lists