From 10bc8e4af65946b727728d7479c028742321b60a Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Thu, 17 Nov 2022 22:52:49 +0200 Subject: vfs: fix copy_file_range() averts filesystem freeze protection Commit 868f9f2f8e00 ("vfs: fix copy_file_range() regression in cross-fs copies") removed fallback to generic_copy_file_range() for cross-fs cases inside vfs_copy_file_range(). To preserve behavior of nfsd and ksmbd server-side-copy, the fallback to generic_copy_file_range() was added in nfsd and ksmbd code, but that call is missing sb_start_write(), fsnotify hooks and more. Ideally, nfsd and ksmbd would pass a flag to vfs_copy_file_range() that will take care of the fallback, but that code would be subtle and we got vfs_copy_file_range() logic wrong too many times already. Instead, add a flag to explicitly request vfs_copy_file_range() to perform only generic_copy_file_range() and let nfsd and ksmbd use this flag only in the fallback path. This choise keeps the logic changes to minimum in the non-nfsd/ksmbd code paths to reduce the risk of further regressions. Fixes: 868f9f2f8e00 ("vfs: fix copy_file_range() regression in cross-fs copies") Tested-by: Namjae Jeon Tested-by: Luis Henriques Signed-off-by: Amir Goldstein Signed-off-by: Al Viro --- fs/nfsd/vfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/nfsd/vfs.c') diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index f650afedd67f..5cf11cde51f8 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -596,8 +596,8 @@ ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst, ret = vfs_copy_file_range(src, src_pos, dst, dst_pos, count, 0); if (ret == -EOPNOTSUPP || ret == -EXDEV) - ret = generic_copy_file_range(src, src_pos, dst, dst_pos, - count, 0); + ret = vfs_copy_file_range(src, src_pos, dst, dst_pos, count, + COPY_FILE_SPLICE); return ret; } -- cgit v1.2.3