From: Xiubo Li <xiubli@xxxxxxxxxx> When releasing the file locks the fl->fl_file memory could be already released by another thread in filp_close(), so we couldn't depend on fl->fl_file to get the inode. Just use a xarray to record the opened files for each inode. Cc: stable@xxxxxxxxxxxxxxx URL: https://tracker.ceph.com/issues/57986 Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx> --- fs/ceph/file.c | 9 +++++++++ fs/ceph/inode.c | 4 ++++ fs/ceph/locks.c | 17 ++++++++++++++++- fs/ceph/super.h | 4 ++++ 4 files changed, 33 insertions(+), 1 deletion(-) diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 85afcbbb5648..cb4a9c52df27 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -231,6 +231,13 @@ static int ceph_init_file_info(struct inode *inode, struct file *file, fi->flags |= CEPH_F_SYNC; file->private_data = fi; + + ret = xa_insert(&ci->i_opened_files, (unsigned long)file, + CEPH_FILP_AVAILABLE, GFP_KERNEL); + if (ret) { + kmem_cache_free(ceph_file_cachep, fi); + return ret; + } } ceph_get_fmode(ci, fmode, 1); @@ -932,6 +939,8 @@ int ceph_release(struct inode *inode, struct file *file) dout("release inode %p regular file %p\n", inode, file); WARN_ON(!list_empty(&fi->rw_contexts)); + xa_erase(&ci->i_opened_files, (unsigned long)file); + ceph_fscache_unuse_cookie(inode, file->f_mode & FMODE_WRITE); ceph_put_fmode(ci, fi->fmode, 1); diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index 77b0cd9af370..554450838e44 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -619,6 +619,8 @@ struct inode *ceph_alloc_inode(struct super_block *sb) INIT_LIST_HEAD(&ci->i_unsafe_iops); spin_lock_init(&ci->i_unsafe_lock); + xa_init(&ci->i_opened_files); + ci->i_snap_realm = NULL; INIT_LIST_HEAD(&ci->i_snap_realm_item); INIT_LIST_HEAD(&ci->i_snap_flush_item); @@ -637,6 +639,8 @@ void ceph_free_inode(struct inode *inode) { struct ceph_inode_info *ci = ceph_inode(inode); + xa_destroy(&ci->i_opened_files); + kfree(ci->i_symlink); #ifdef CONFIG_FS_ENCRYPTION kfree(ci->fscrypt_auth); diff --git a/fs/ceph/locks.c b/fs/ceph/locks.c index d8385dd0076e..a176a30badd0 100644 --- a/fs/ceph/locks.c +++ b/fs/ceph/locks.c @@ -42,9 +42,10 @@ static void ceph_fl_copy_lock(struct file_lock *dst, struct file_lock *src) static void ceph_fl_release_lock(struct file_lock *fl) { - struct ceph_file_info *fi = fl->fl_file->private_data; struct inode *inode = fl->fl_u.ceph_fl.fl_inode; struct ceph_inode_info *ci; + struct ceph_file_info *fi; + void *val; /* * If inode is NULL it should be a request file_lock, @@ -54,6 +55,20 @@ static void ceph_fl_release_lock(struct file_lock *fl) return; ci = ceph_inode(inode); + + /* + * For Posix-style locks, it may race between filp_close()s, + * and it's possible that the 'file' memory pointed by + * 'fl->fl_file' has been released. If so just skip it. + */ + rcu_read_lock(); + val = xa_load(&ci->i_opened_files, (unsigned long)fl->fl_file); + if (val == CEPH_FILP_AVAILABLE) { + fi = fl->fl_file->private_data; + atomic_dec(&fi->num_locks); + } + rcu_read_unlock(); + if (atomic_dec_and_test(&ci->i_filelock_ref)) { /* clear error when all locks are released */ spin_lock(&ci->i_ceph_lock); diff --git a/fs/ceph/super.h b/fs/ceph/super.h index 7b75a84ba48d..b3e89192cbec 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -329,6 +329,8 @@ struct ceph_inode_xattrs_info { u64 version, index_version; }; +#define CEPH_FILP_AVAILABLE xa_mk_value(1) + /* * Ceph inode. */ @@ -434,6 +436,8 @@ struct ceph_inode_info { struct list_head i_unsafe_iops; /* uncommitted mds inode ops */ spinlock_t i_unsafe_lock; + struct xarray i_opened_files; + union { struct ceph_snap_realm *i_snap_realm; /* snap realm (if caps) */ struct ceph_snapid_map *i_snapid_map; /* snapid -> dev_t */ -- 2.31.1
