From dec8980573d56795bd10396d0155d9f7f4d848e5 Mon Sep 17 00:00:00 2001 From: Zhang Yi Date: Thu, 30 Jun 2022 17:01:00 +0800 Subject: [PATCH] ext4: fix reading leftover inlined symlinks Since commit 0f488c1e59f5 ("ext4: convert symlink external data block mapping to bdev"), create new symlink with inline_data is not supported, but it missing to handle the leftover inlined symlinks, which could cause below error message and fail to read symlink. ls: cannot read symbolic link 'foo': Structure needs cleaning EXT4-fs error (device sda): ext4_map_blocks:605: inode #12: block 2021161080: comm ls: lblock 0 mapped to illegal pblock 2021161080 (length 1) Fix this regression by adding ext4_read_inline_link(), which read the inline data directly and convert it through a kmalloced buffer. Fixes: 0f488c1e59f5 ("ext4: convert symlink external data block mapping to bdev") Cc: stable@kernel.org Reported-by: Torge Matthies Signed-off-by: Zhang Yi Tested-by: Torge Matthies Link: https://lore.kernel.org/r/20220630090100.2769490-1-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o --- fs/ext4/ext4.h | 1 + fs/ext4/inline.c | 30 ++++++++++++++++++++++++++++++ fs/ext4/symlink.c | 15 +++++++++++++++ 3 files changed, 46 insertions(+) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 75b8d81b24692..adfc30ee4b7be 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -3583,6 +3583,7 @@ extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode, extern int ext4_inline_data_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, int *has_inline, __u64 start, __u64 len); +extern void *ext4_read_inline_link(struct inode *inode); struct iomap; extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap); diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c index cff52ff6549d2..1fa36cbe09ecc 100644 --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -6,6 +6,7 @@ #include #include +#include #include #include @@ -1588,6 +1589,35 @@ out: return ret; } +void *ext4_read_inline_link(struct inode *inode) +{ + struct ext4_iloc iloc; + int ret, inline_size; + void *link; + + ret = ext4_get_inode_loc(inode, &iloc); + if (ret) + return ERR_PTR(ret); + + ret = -ENOMEM; + inline_size = ext4_get_inline_size(inode); + link = kmalloc(inline_size + 1, GFP_NOFS); + if (!link) + goto out; + + ret = ext4_read_inline_data(inode, link, inline_size, &iloc); + if (ret < 0) { + kfree(link); + goto out; + } + nd_terminate_link(link, inode->i_size, ret); +out: + if (ret < 0) + link = ERR_PTR(ret); + brelse(iloc.bh); + return link; +} + struct buffer_head *ext4_get_first_inline_block(struct inode *inode, struct ext4_dir_entry_2 **parent_de, int *retval) diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c index d281f5bcc5264..3d3ed3c38f564 100644 --- a/fs/ext4/symlink.c +++ b/fs/ext4/symlink.c @@ -74,6 +74,21 @@ static const char *ext4_get_link(struct dentry *dentry, struct inode *inode, struct delayed_call *callback) { struct buffer_head *bh; + char *inline_link; + + /* + * Create a new inlined symlink is not supported, just provide a + * method to read the leftovers. + */ + if (ext4_has_inline_data(inode)) { + if (!dentry) + return ERR_PTR(-ECHILD); + + inline_link = ext4_read_inline_link(inode); + if (!IS_ERR(inline_link)) + set_delayed_call(callback, kfree_link, inline_link); + return inline_link; + } if (!dentry) { bh = ext4_getblk(NULL, inode, 0, EXT4_GET_BLOCKS_CACHED_NOWAIT); -- 2.39.5