From 27d17652f12c4bb98d1c3e530b221bade44b9f9f Mon Sep 17 00:00:00 2001 From: Alessio Balsini Date: Thu, 23 Sep 2021 11:05:08 +0100 Subject: [PATCH] ANDROID: fs/fuse: Keep FUSE file times consistent with lower file When FUSE passthrough is used, the lower file system file is manipulated directly, but neither mtime, atime or ctime of the referencing FUSE file is updated. Fix by updating the file times when passthrough operations are performed. Bug: 200779468 Bug: 201730208 Reported-by: Fengnan Chang Reported-by: Ed Tsai Signed-off-by: Alessio Balsini Change-Id: I35b72196b2cc1d79a9f62ddb32e2cfa934c3b6d3 --- fs/fuse/passthrough.c | 41 ++++++++++++++++++++++++++++------------- 1 file changed, 28 insertions(+), 13 deletions(-) diff --git a/fs/fuse/passthrough.c b/fs/fuse/passthrough.c index 5fa11d708e59..814b9a5a3beb 100644 --- a/fs/fuse/passthrough.c +++ b/fs/fuse/passthrough.c @@ -26,11 +26,34 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src, }; } +static void fuse_file_accessed(struct file *dst_file, struct file *src_file) +{ + struct inode *dst_inode; + struct inode *src_inode; + + if (dst_file->f_flags & O_NOATIME) + return; + + dst_inode = file_inode(dst_file); + src_inode = file_inode(src_file); + + if ((!timespec64_equal(&dst_inode->i_mtime, &src_inode->i_mtime) || + !timespec64_equal(&dst_inode->i_ctime, &src_inode->i_ctime))) { + dst_inode->i_mtime = src_inode->i_mtime; + dst_inode->i_ctime = src_inode->i_ctime; + } + + touch_atime(&dst_file->f_path); +} + static void fuse_copyattr(struct file *dst_file, struct file *src_file) { struct inode *dst = file_inode(dst_file); struct inode *src = file_inode(src_file); + dst->i_atime = src->i_atime; + dst->i_mtime = src->i_mtime; + dst->i_ctime = src->i_ctime; i_size_write(dst, i_size_read(src)); } @@ -96,6 +119,8 @@ ssize_t fuse_passthrough_read_iter(struct kiocb *iocb_fuse, out: revert_creds(old_cred); + fuse_file_accessed(fuse_filp, passthrough_filp); + return ret; } @@ -115,6 +140,8 @@ ssize_t fuse_passthrough_write_iter(struct kiocb *iocb_fuse, inode_lock(fuse_inode); + fuse_copyattr(fuse_filp, passthrough_filp); + old_cred = override_creds(ff->passthrough.cred); if (is_sync_kiocb(iocb_fuse)) { file_start_write(passthrough_filp); @@ -155,9 +182,7 @@ ssize_t fuse_passthrough_mmap(struct file *file, struct vm_area_struct *vma) int ret; const struct cred *old_cred; struct fuse_file *ff = file->private_data; - struct inode *fuse_inode = file_inode(file); struct file *passthrough_filp = ff->passthrough.filp; - struct inode *passthrough_inode = file_inode(passthrough_filp); if (!passthrough_filp->f_op->mmap) return -ENODEV; @@ -176,17 +201,7 @@ ssize_t fuse_passthrough_mmap(struct file *file, struct vm_area_struct *vma) else fput(file); - if (file->f_flags & O_NOATIME) - return ret; - - if ((!timespec64_equal(&fuse_inode->i_mtime, - &passthrough_inode->i_mtime) || - !timespec64_equal(&fuse_inode->i_ctime, - &passthrough_inode->i_ctime))) { - fuse_inode->i_mtime = passthrough_inode->i_mtime; - fuse_inode->i_ctime = passthrough_inode->i_ctime; - } - touch_atime(&file->f_path); + fuse_file_accessed(file, passthrough_filp); return ret; }