diff mbox series

[09/13] procfs: move dropping pde and pid from ->evict_inode() to ->free_inode()

Message ID 20240204021739.1157830-9-viro@zeniv.linux.org.uk (mailing list archive)
State New
Headers show
Series [01/13] fs/super.c: don't drop ->s_user_ns until we free struct super_block itself | expand

Commit Message

Al Viro Feb. 4, 2024, 2:17 a.m. UTC 
that keeps both around until struct inode is freed, making access
to them safe from rcu-pathwalk

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/proc/base.c  |  2 --
 fs/proc/inode.c | 19 ++++++++-----------
 2 files changed, 8 insertions(+), 13 deletions(-)

Comments

Christian Brauner Feb. 5, 2024, 12:30 p.m. UTC | #1 
On Sun, Feb 04, 2024 at 02:17:35AM +0000, Al Viro wrote:
> that keeps both around until struct inode is freed, making access
> to them safe from rcu-pathwalk
> 
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> ---

Acked-by: Christian Brauner <brauner@kernel.org>
diff mbox series

Patch

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 98a031ac2648..18550c071d71 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1878,8 +1878,6 @@  void proc_pid_evict_inode(struct proc_inode *ei)
 		hlist_del_init_rcu(&ei->sibling_inodes);
 		spin_unlock(&pid->lock);
 	}
-
-	put_pid(pid);
 }
 
 struct inode *proc_pid_make_inode(struct super_block *sb,
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index b33e490e3fd9..05350f3c2812 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -30,7 +30,6 @@ 
 
 static void proc_evict_inode(struct inode *inode)
 {
-	struct proc_dir_entry *de;
 	struct ctl_table_header *head;
 	struct proc_inode *ei = PROC_I(inode);
 
@@ -38,17 +37,8 @@  static void proc_evict_inode(struct inode *inode)
 	clear_inode(inode);
 
 	/* Stop tracking associated processes */
-	if (ei->pid) {
+	if (ei->pid)
 		proc_pid_evict_inode(ei);
-		ei->pid = NULL;
-	}
-
-	/* Let go of any associated proc directory entry */
-	de = ei->pde;
-	if (de) {
-		pde_put(de);
-		ei->pde = NULL;
-	}
 
 	head = ei->sysctl;
 	if (head) {
@@ -80,6 +70,13 @@  static struct inode *proc_alloc_inode(struct super_block *sb)
 
 static void proc_free_inode(struct inode *inode)
 {
+	struct proc_inode *ei = PROC_I(inode);
+
+	if (ei->pid)
+		put_pid(ei->pid);
+	/* Let go of any associated proc directory entry */
+	if (ei->pde)
+		pde_put(ei->pde);
 	kmem_cache_free(proc_inode_cachep, PROC_I(inode));
 }