The patch titled
unionfs: fix slab abuses with krealloc
has been removed from the -mm tree. Its filename was
unionfs-fix-slab-abuses-with-krealloc.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
Subject: unionfs: fix slab abuses with krealloc
From: Pekka Enberg <penberg@xxxxxxxxxxxxxx>
This changes unionfs to use krealloc() for reallocating memory so that we
don't need to play tricks with slab internals.
Cc: Josef Sipek <jsipek@xxxxxxxxxxxxxxxxx>
Signed-off-by: Pekka Enberg <penberg@xxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/Kconfig | 2 +-
fs/unionfs/copyup.c | 35 +++++++++++++----------------------
fs/unionfs/lookup.c | 34 ++++++++++++++--------------------
3 files changed, 28 insertions(+), 43 deletions(-)
diff -puN fs/Kconfig~unionfs-fix-slab-abuses-with-krealloc fs/Kconfig
--- a/fs/Kconfig~unionfs-fix-slab-abuses-with-krealloc
+++ a/fs/Kconfig
@@ -1071,7 +1071,7 @@ config ECRYPT_FS
config UNION_FS
tristate "Union file system (EXPERIMENTAL)"
- depends on SLAB && EXPERIMENTAL
+ depends on EXPERIMENTAL
help
Unionfs is a stackable unification file system, which appears to
merge the contents of several directories (branches), while keeping
diff -puN fs/unionfs/copyup.c~unionfs-fix-slab-abuses-with-krealloc fs/unionfs/copyup.c
--- a/fs/unionfs/copyup.c~unionfs-fix-slab-abuses-with-krealloc
+++ a/fs/unionfs/copyup.c
@@ -618,23 +618,16 @@ static struct dentry *create_parents_nam
const char *childname;
unsigned int childnamelen;
- int old_kmalloc_size;
- int kmalloc_size;
- int num_dentry;
+ int nr_dentry;
int count;
int old_bstart;
int old_bend;
struct dentry **path = NULL;
- struct dentry **tmp_path;
struct super_block *sb;
verify_locked(dentry);
- /* There is no sense allocating any less than the minimum. */
- kmalloc_size = malloc_sizes[0].cs_size;
- num_dentry = kmalloc_size / sizeof(struct dentry *);
-
if ((err = is_robranch_super(dir->i_sb, bindex))) {
hidden_dentry = ERR_PTR(err);
goto out;
@@ -644,7 +637,10 @@ static struct dentry *create_parents_nam
old_bend = dbend(dentry);
hidden_dentry = ERR_PTR(-ENOMEM);
- path = kzalloc(kmalloc_size, GFP_KERNEL);
+
+ /* There is no sense allocating any less than the minimum. */
+ nr_dentry = 1;
+ path = kmalloc(nr_dentry * sizeof(struct dentry *), GFP_KERNEL);
if (!path)
goto out;
@@ -670,26 +666,21 @@ static struct dentry *create_parents_nam
/* find out the hidden_parent_dentry in the given branch */
hidden_parent_dentry = unionfs_lower_dentry_idx(parent_dentry, bindex);
- /* store the child dentry */
- path[count++] = child_dentry;
-
/* grow path table */
- if (count == num_dentry) {
- old_kmalloc_size = kmalloc_size;
- kmalloc_size *= 2;
- num_dentry = kmalloc_size / sizeof(struct dentry *);
+ if (count == nr_dentry) {
+ void *p;
- tmp_path = kzalloc(kmalloc_size, GFP_KERNEL);
- if (!tmp_path) {
+ nr_dentry *= 2;
+ p = krealloc(path, nr_dentry * sizeof(struct dentry *), GFP_KERNEL);
+ if (!p) {
hidden_dentry = ERR_PTR(-ENOMEM);
goto out;
}
- memcpy(tmp_path, path, old_kmalloc_size);
- kfree(path);
- path = tmp_path;
- tmp_path = NULL;
+ path = p;
}
+ /* store the child dentry */
+ path[count++] = child_dentry;
} while (!hidden_parent_dentry);
count--;
diff -puN fs/unionfs/lookup.c~unionfs-fix-slab-abuses-with-krealloc fs/unionfs/lookup.c
--- a/fs/unionfs/lookup.c~unionfs-fix-slab-abuses-with-krealloc
+++ a/fs/unionfs/lookup.c
@@ -432,8 +432,8 @@ void free_dentry_private_data(struct uni
/* allocate new dentry private data, free old one if necessary */
int new_dentry_private_data(struct dentry *dentry)
{
- int newsize;
- int oldsize = 0;
+ int new_size;
+ int size;
struct unionfs_dentry_info *info = UNIONFS_D(dentry);
int unlock_on_err = 0;
@@ -451,8 +451,9 @@ int new_dentry_private_data(struct dentr
unlock_on_err = 1;
info->lower_paths = NULL;
+ size = 0;
} else
- oldsize = sizeof(struct path) * info->bcount;
+ size = sizeof(struct path) * info->bcount;
info->bstart = -1;
info->bend = -1;
@@ -460,28 +461,21 @@ int new_dentry_private_data(struct dentr
info->bcount = sbmax(dentry->d_sb);
atomic_set(&info->generation,
atomic_read(&UNIONFS_SB(dentry->d_sb)->generation));
- newsize = sizeof(struct path) * sbmax(dentry->d_sb);
+
+ new_size = sizeof(struct path) * sbmax(dentry->d_sb);
/* Don't reallocate when we already have enough space. */
- /* It would be ideal if we could actually use the slab macros to
- * determine what our object sizes is, but those are not exported.
- */
- if (oldsize) {
- int minsize = malloc_sizes[0].cs_size;
-
- if (!newsize || ((oldsize < newsize) && (newsize > minsize))) {
- kfree(info->lower_paths);
- info->lower_paths = NULL;
- }
- }
+ if (new_size > size) {
+ void *p;
- if (!info->lower_paths && newsize) {
- info->lower_paths = kmalloc(newsize, GFP_ATOMIC);
- if (!info->lower_paths)
+ p = krealloc(info->lower_paths, new_size, GFP_ATOMIC);
+ if (!p)
goto out_free;
- }
- memset(info->lower_paths, 0, (oldsize > newsize ? oldsize : newsize));
+ info->lower_paths = p;
+ size = new_size;
+ }
+ memset(info->lower_paths, 0, size);
spin_unlock(&dentry->d_lock);
return 0;
_
Patches currently in -mm which might be from penberg@xxxxxxxxxxxxxx are
git-unionfs.patch
slab-allocators-drop-support-for-destructors.patch
revoke-special-mmap-handling.patch
revoke-special-mmap-handling-vs-fault-vs-invalidate.patch
revoke-core-code.patch
revoke-support-for-ext2-and-ext3.patch
revoke-add-documentation.patch
revoke-wire-up-i386-system-calls.patch
slab-leaks3-default-y.patch
-
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