[patch 01/42] cramfs: fix named-pipe handling

From: Greg KH
Date: Wed Sep 03 2008 - 13:31:50 EST


2.6.26-stable review patch. If anyone has any objections, please let us know.

------------------

From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

commit 82d63fc9e30687c055b97928942b8893ea65b0bb upstream

After commit a97c9bf33f4612e2aed6f000f6b1d268b6814f3c (fix cramfs
making duplicate entries in inode cache) in kernel 2.6.14, named-pipe
on cramfs does not work properly.

It seems the commit make all named-pipe on cramfs share their inode
(and named-pipe buffer).

Make ..._test() refuse to merge inodes with ->i_ino == 1, take inode setup
back to get_cramfs_inode() and make ->drop_inode() evict ones with ->i_ino
== 1 immediately.

Reported-by: Atsushi Nemoto <anemo@xxxxxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
fs/cramfs/inode.c | 84 ++++++++++++++++++++++++------------------------------
1 file changed, 38 insertions(+), 46 deletions(-)

--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -43,58 +43,13 @@ static DEFINE_MUTEX(read_mutex);
static int cramfs_iget5_test(struct inode *inode, void *opaque)
{
struct cramfs_inode *cramfs_inode = opaque;
-
- if (inode->i_ino != CRAMINO(cramfs_inode))
- return 0; /* does not match */
-
- if (inode->i_ino != 1)
- return 1;
-
- /* all empty directories, char, block, pipe, and sock, share inode #1 */
-
- if ((inode->i_mode != cramfs_inode->mode) ||
- (inode->i_gid != cramfs_inode->gid) ||
- (inode->i_uid != cramfs_inode->uid))
- return 0; /* does not match */
-
- if ((S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) &&
- (inode->i_rdev != old_decode_dev(cramfs_inode->size)))
- return 0; /* does not match */
-
- return 1; /* matches */
+ return inode->i_ino == CRAMINO(cramfs_inode) && inode->i_ino != 1;
}

static int cramfs_iget5_set(struct inode *inode, void *opaque)
{
- static struct timespec zerotime;
struct cramfs_inode *cramfs_inode = opaque;
- inode->i_mode = cramfs_inode->mode;
- inode->i_uid = cramfs_inode->uid;
- inode->i_size = cramfs_inode->size;
- inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1;
- inode->i_gid = cramfs_inode->gid;
- /* Struct copy intentional */
- inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime;
inode->i_ino = CRAMINO(cramfs_inode);
- /* inode->i_nlink is left 1 - arguably wrong for directories,
- but it's the best we can do without reading the directory
- contents. 1 yields the right result in GNU find, even
- without -noleaf option. */
- if (S_ISREG(inode->i_mode)) {
- inode->i_fop = &generic_ro_fops;
- inode->i_data.a_ops = &cramfs_aops;
- } else if (S_ISDIR(inode->i_mode)) {
- inode->i_op = &cramfs_dir_inode_operations;
- inode->i_fop = &cramfs_directory_operations;
- } else if (S_ISLNK(inode->i_mode)) {
- inode->i_op = &page_symlink_inode_operations;
- inode->i_data.a_ops = &cramfs_aops;
- } else {
- inode->i_size = 0;
- inode->i_blocks = 0;
- init_special_inode(inode, inode->i_mode,
- old_decode_dev(cramfs_inode->size));
- }
return 0;
}

@@ -104,12 +59,48 @@ static struct inode *get_cramfs_inode(st
struct inode *inode = iget5_locked(sb, CRAMINO(cramfs_inode),
cramfs_iget5_test, cramfs_iget5_set,
cramfs_inode);
+ static struct timespec zerotime;
+
if (inode && (inode->i_state & I_NEW)) {
+ inode->i_mode = cramfs_inode->mode;
+ inode->i_uid = cramfs_inode->uid;
+ inode->i_size = cramfs_inode->size;
+ inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1;
+ inode->i_gid = cramfs_inode->gid;
+ /* Struct copy intentional */
+ inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime;
+ /* inode->i_nlink is left 1 - arguably wrong for directories,
+ but it's the best we can do without reading the directory
+ contents. 1 yields the right result in GNU find, even
+ without -noleaf option. */
+ if (S_ISREG(inode->i_mode)) {
+ inode->i_fop = &generic_ro_fops;
+ inode->i_data.a_ops = &cramfs_aops;
+ } else if (S_ISDIR(inode->i_mode)) {
+ inode->i_op = &cramfs_dir_inode_operations;
+ inode->i_fop = &cramfs_directory_operations;
+ } else if (S_ISLNK(inode->i_mode)) {
+ inode->i_op = &page_symlink_inode_operations;
+ inode->i_data.a_ops = &cramfs_aops;
+ } else {
+ inode->i_size = 0;
+ inode->i_blocks = 0;
+ init_special_inode(inode, inode->i_mode,
+ old_decode_dev(cramfs_inode->size));
+ }
unlock_new_inode(inode);
}
return inode;
}

+static void cramfs_drop_inode(struct inode *inode)
+{
+ if (inode->i_ino == 1)
+ generic_delete_inode(inode);
+ else
+ generic_drop_inode(inode);
+}
+
/*
* We have our own block cache: don't fill up the buffer cache
* with the rom-image, because the way the filesystem is set
@@ -534,6 +525,7 @@ static const struct super_operations cra
.put_super = cramfs_put_super,
.remount_fs = cramfs_remount,
.statfs = cramfs_statfs,
+ .drop_inode = cramfs_drop_inode,
};

static int cramfs_get_sb(struct file_system_type *fs_type,

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