RedHat in RHEL9.4 has backported overlayfs data-only lower layers
feature (ms commit 37ebf056d6cf ("ovl: introduce data-only lower
layers")), so we have to adjust our dynamic path resolving feature.
Additionally store number of lowerpaths as it now differs from saved
number of lowerstacks due to data-only lower layers presence.
Fixes: 5f2c7b5e4d33 ("overlayfs: add dynamic path resolving in mount
options")
https://virtuozzo.atlassian.net/browse/PSBM-157244
Signed-off-by: Konstantin Khorenko <khore...@virtuozzo.com>
---
fs/overlayfs/overlayfs.h | 2 +-
fs/overlayfs/ovl_entry.h | 13 ++++++++++++-
fs/overlayfs/super.c | 9 ++++++---
fs/overlayfs/util.c | 21 ++++++++++++++++++---
4 files changed, 37 insertions(+), 8 deletions(-)
v2 changes:
* ovl_free_entry() appeared to be not the only way to free ovl_entry,
the second function is ovl_free_inode(), so include the kfree() there
as well
* create a single function ovl_stacks_put() for both lowerstack and
lowerpaths put and rename ovl_stack_put() to prevent desync in the
future
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 163858e97e89..2e7aa23eb755 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -402,7 +402,7 @@ bool ovl_index_all(struct super_block *sb);
bool ovl_verify_lower(struct super_block *sb);
struct ovl_path *ovl_stack_alloc(unsigned int n);
void ovl_stack_cpy(struct ovl_path *dst, struct ovl_path *src, unsigned int n);
-void ovl_stack_put(struct ovl_path *stack, unsigned int n);
+void ovl_stacks_put(struct ovl_entry *oe);
void ovl_stack_free(struct ovl_path *stack, unsigned int n);
struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
void ovl_free_entry(struct ovl_entry *oe);
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index f30de89e1f72..9d95ccdb3e3f 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -52,8 +52,9 @@ struct ovl_path {
};
struct ovl_entry {
+ unsigned int __numlowerpaths;
unsigned int __numlower;
- struct path *lowerpaths;
+ struct path *__lowerpaths;
struct ovl_path __lowerstack[];
};
@@ -125,6 +126,16 @@ static inline bool ovl_should_sync(struct ovl_fs *ofs)
return !ofs->config.ovl_volatile;
}
+static inline unsigned int ovl_numlowerpaths(struct ovl_entry *oe)
+{
+ return oe ? oe->__numlowerpaths : 0;
+}
+
+static inline struct path *ovl_lowerpaths(struct ovl_entry *oe)
+{
+ return ovl_numlowerpaths(oe) ? oe->__lowerpaths : NULL;
+}
+
static inline unsigned int ovl_numlower(struct ovl_entry *oe)
{
return oe ? oe->__numlower : 0;
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index e9e8602291e0..2aeec05c1a34 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -213,6 +213,7 @@ static void ovl_free_inode(struct inode *inode)
struct ovl_inode *oi = OVL_I(inode);
kfree(oi->redirect);
+ kfree(ovl_lowerpaths(oi->oe));
kfree(oi->oe);
mutex_destroy(&oi->lock);
kmem_cache_free(ovl_inode_cachep, oi);
@@ -223,7 +224,7 @@ static void ovl_destroy_inode(struct inode *inode)
struct ovl_inode *oi = OVL_I(inode);
dput(oi->__upperdentry);
- ovl_stack_put(ovl_lowerstack(oi->oe), ovl_numlower(oi->oe));
+ ovl_stacks_put(oi->oe);
if (S_ISDIR(inode->i_mode))
ovl_dir_cache_free(inode);
else
@@ -386,7 +387,8 @@ static int ovl_show_options(struct seq_file *m, struct
dentry *dentry)
struct ovl_entry *oe = OVL_E(sb->s_root);
if (ovl_dyn_path_opts) {
- print_paths_option(m, "lowerdir", oe->lowerpaths,
ovl_numlower(oe));
+ print_paths_option(m, "lowerdir", ovl_lowerpaths(oe),
+ ovl_numlowerpaths(oe));
if (ofs->config.upperdir) {
print_path_option(m, "upperdir", &ofs->upperpath);
print_path_option(m, "workdir", &ofs->workbasepath);
@@ -1854,7 +1856,8 @@ static struct ovl_entry *ovl_get_lowerstack(struct
super_block *sb,
lowerstack[i].dentry = dget(stack[i].dentry);
lowerstack[i].layer = &ofs->layers[i+1];
}
- oe->lowerpaths = stack;
+ oe->__numlowerpaths = numlower;
+ oe->__lowerpaths = stack;
out:
return oe;
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 3676eaa83f7d..21acc780ebfc 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -100,7 +100,7 @@ void ovl_stack_cpy(struct ovl_path *dst, struct ovl_path
*src, unsigned int n)
dget(src[i].dentry);
}
-void ovl_stack_put(struct ovl_path *stack, unsigned int n)
+void __ovl_stack_put(struct ovl_path *stack, unsigned int n)
{
unsigned int i;
@@ -110,10 +110,24 @@ void ovl_stack_put(struct ovl_path *stack, unsigned int n)
void ovl_stack_free(struct ovl_path *stack, unsigned int n)
{
- ovl_stack_put(stack, n);
+ __ovl_stack_put(stack, n);
kfree(stack);
}
+void __ovl_lowerpaths_put(struct path *lowerpaths, unsigned int n)
+{
+ unsigned int i;
+
+ for (i = 0; i < n; i++)
+ path_put(&lowerpaths[i]);
+}
+
+void ovl_stacks_put(struct ovl_entry *oe)
+{
+ __ovl_stack_put(ovl_lowerstack(oe), ovl_numlower(oe));
+ __ovl_lowerpaths_put(ovl_lowerpaths(oe), ovl_numlowerpaths(oe));
+}
+
struct ovl_entry *ovl_alloc_entry(unsigned int numlower)
{
size_t size = offsetof(struct ovl_entry, __lowerstack[numlower]);
@@ -127,7 +141,8 @@ struct ovl_entry *ovl_alloc_entry(unsigned int numlower)
void ovl_free_entry(struct ovl_entry *oe)
{
- ovl_stack_put(ovl_lowerstack(oe), ovl_numlower(oe));
+ ovl_stacks_put(oe);
+ kfree(ovl_lowerpaths(oe));
kfree(oe);
}
--
2.43.5
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