From: Zhang Yi <yi.zhang@xxxxxxxxxx>
[ Upstream commit 5a57bca9050d740ca37184302e23d0e7633e3ebc ]
Since commit 6493792d3299 ("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: 6493792d3299 ("ext4: convert symlink external data block mapping to bdev")
Cc: stable@xxxxxxxxxx
Reported-by: Torge Matthies <openglfreak@xxxxxxxxxxxxxx>
Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
Tested-by: Torge Matthies <openglfreak@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220630090100.2769490-1-yi.zhang@xxxxxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 75b8d81b2469..adfc30ee4b7b 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 cff52ff6549d..1fa36cbe09ec 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -6,6 +6,7 @@
#include <linux/iomap.h>
#include <linux/fiemap.h>
+#include <linux/namei.h>
#include <linux/iversion.h>
#include <linux/sched/mm.h>
@@ -1588,6 +1589,35 @@ int ext4_read_inline_dir(struct file *file,
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 d281f5bcc526..3d3ed3c38f56 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);
--
2.35.1
