Re: [PATCH v2 30/54] fs: change evict_dentries_for_decrypted_inodes to use refcount
From: Christian Brauner <brauner@kernel.org>
Date: 2025-08-28 12:25:25
Also in:
linux-btrfs, linux-fsdevel, linux-xfs
On Tue, Aug 26, 2025 at 11:39:30AM -0400, Josef Bacik wrote:
Instead of checking for I_WILL_FREE|I_FREEING simply use the refcount to make sure we have a live inode. Signed-off-by: Josef Bacik <josef@toxicpanda.com> ---
I have no idea how the lifetime of such decrypted inodes are managed. I suppose they don't carry a separate reference but are still somehow safe to be accessed based on the mk_decrypted_inodes list. In any case something must hold an i_obj_count if we want to use igrab() since I don't see any relevant rcu protection here.
quoted hunk ↗ jump to hunk
fs/crypto/keyring.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)diff --git a/fs/crypto/keyring.c b/fs/crypto/keyring.c index 7557f6a88b8f..969db498149a 100644 --- a/fs/crypto/keyring.c +++ b/fs/crypto/keyring.c@@ -956,13 +956,16 @@ static void evict_dentries_for_decrypted_inodes(struct fscrypt_master_key *mk) list_for_each_entry(ci, &mk->mk_decrypted_inodes, ci_master_key_link) { inode = ci->ci_inode; + spin_lock(&inode->i_lock); - if (inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW)) { + if (inode->i_state & I_NEW) { spin_unlock(&inode->i_lock); continue; } - __iget(inode); spin_unlock(&inode->i_lock); + + if (!igrab(inode)) + continue; spin_unlock(&mk->mk_decrypted_inodes_lock); shrink_dcache_inode(inode);-- 2.49.0