Amir Goldstein 4d5055873e vfs: fix copy_file_range() regression in cross-fs copies ... commit 868f9f2f8e upstream. A regression has been reported by Nicolas Boichat, found while using the copy_file_range syscall to copy a tracefs file. Before commit 5dae222a5f ("vfs: allow copy_file_range to copy across devices") the kernel would return -EXDEV to userspace when trying to copy a file across different filesystems. After this commit, the syscall doesn't fail anymore and instead returns zero (zero bytes copied), as this file's content is generated on-the-fly and thus reports a size of zero. Another regression has been reported by He Zhe - the assertion of WARN_ON_ONCE(ret == -EOPNOTSUPP) can be triggered from userspace when copying from a sysfs file whose read operation may return -EOPNOTSUPP. Since we do not have test coverage for copy_file_range() between any two types of filesystems, the best way to avoid these sort of issues in the future is for the kernel to be more picky about filesystems that are allowed to do copy_file_range(). This patch restores some cross-filesystem copy restrictions that existed prior to commit 5dae222a5f ("vfs: allow copy_file_range to copy across devices"), namely, cross-sb copy is not allowed for filesystems that do not implement ->copy_file_range(). Filesystems that do implement ->copy_file_range() have full control of the result - if this method returns an error, the error is returned to the user. Before this change this was only true for fs that did not implement the ->remap_file_range() operation (i.e. nfsv3). Filesystems that do not implement ->copy_file_range() still fall-back to the generic_copy_file_range() implementation when the copy is within the same sb. This helps the kernel can maintain a more consistent story about which filesystems support copy_file_range(). nfsd and ksmbd servers are modified to fall-back to the generic_copy_file_range() implementation in case vfs_copy_file_range() fails with -EOPNOTSUPP or -EXDEV, which preserves behavior of server-side-copy. fall-back to generic_copy_file_range() is not implemented for the smb operation FSCTL_DUPLICATE_EXTENTS_TO_FILE, which is arguably a correct change of behavior. Fixes: 5dae222a5f ("vfs: allow copy_file_range to copy across devices") Link: https://lore.kernel.org/linux-fsdevel/20210212044405.4120619-1-drinkcat@chromium.org/ Link: https://lore.kernel.org/linux-fsdevel/CANMq1KDZuxir2LM5jOTm0xx+BnvW=ZmpsG47CyHFJwnw7zSX6Q@mail.gmail.com/ Link: https://lore.kernel.org/linux-fsdevel/20210126135012.1.If45b7cdc3ff707bc1efa17f5366057d60603c45f@changeid/ Link: https://lore.kernel.org/linux-fsdevel/20210630161320.29006-1-lhenriques@suse.de/ Reported-by: Nicolas Boichat <drinkcat@chromium.org> Reported-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Luis Henriques <lhenriques@suse.de> Fixes: 64bf5ff58d ("vfs: no fallback for ->copy_file_range") Link: https://lore.kernel.org/linux-fsdevel/20f17f64-88cb-4e80-07c1-85cb96c83619@windriver.com/ Reported-by: He Zhe <zhe.he@windriver.com> Tested-by: Namjae Jeon <linkinjeon@kernel.org> Tested-by: Luis Henriques <lhenriques@suse.de> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-07-07 17:53:27 +02:00
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mgmt	…
Kconfig	…
Makefile	…
asn1.c	…
asn1.h	…
auth.c	…
auth.h	…
connection.c	ksmbd: fix outstanding credits related bugs	2022-06-09 10:23:27 +02:00
connection.h	…
crypto_ctx.c	…
crypto_ctx.h	…
glob.h	…
ksmbd_netlink.h	…
ksmbd_spnego_negtokeninit.asn1	…
ksmbd_spnego_negtokentarg.asn1	…
ksmbd_work.c	…
ksmbd_work.h	…
misc.c	…
misc.h	…
ndr.c	…
ndr.h	…
nterr.h	…
ntlmssp.h	…
oplock.c	…
oplock.h	…
server.c	…
server.h	…
smb2misc.c	ksmbd: fix outstanding credits related bugs	2022-06-09 10:23:27 +02:00
smb2ops.c	…
smb2pdu.c	vfs: fix copy_file_range() regression in cross-fs copies	2022-07-07 17:53:27 +02:00
smb2pdu.h	…
smb_common.c	ksmbd: fix outstanding credits related bugs	2022-06-09 10:23:27 +02:00
smb_common.h	…
smbacl.c	fs: use low-level mapping helpers	2022-07-02 16:41:16 +02:00
smbacl.h	fs: use low-level mapping helpers	2022-07-02 16:41:16 +02:00
smbfsctl.h	…
smbstatus.h	…
transport_ipc.c	…
transport_ipc.h	…
transport_rdma.c	…
transport_rdma.h	…
transport_tcp.c	…
transport_tcp.h	…
unicode.c	…
unicode.h	…
uniupr.h	…
vfs.c	vfs: fix copy_file_range() regression in cross-fs copies	2022-07-07 17:53:27 +02:00
vfs.h	…
vfs_cache.c	…
vfs_cache.h	…
xattr.h	…