[PATCH 0/6] cleanup llseek and splice
From: Jason A. Donenfeld
Date: Fri Jun 24 2022 - 12:56:59 EST
The goal of this patchset is to enable splicing to internal pipes for
select chardevs where it makes sense to do so. In the process, however,
it was revealed that many regular files are problematic here. The key
insight is that splicing to internal pipes is okay so long as the splice
operation is rewindable. That means these devices need to be llseekable.
So the series first tries to make llseek a bit tamer, fixing up the
long-standing tension between llseek==NULL vs llseek==no_llseek vs
~FMODE_LSEEK.
Along the way the series also fixes related bugs in ksmbd, dma-buf, and
vfio.
Finally, with FMODE_LSEEK as good information, the series is able to
adjust internal pipe splicing to use that.
Jason A. Donenfeld (6):
ksmbd: use vfs_llseek instead of dereferencing NULL
fs: do not set no_llseek in fops
fs: clear FMODE_LSEEK if no llseek function
fs: check FMODE_LSEEK to control internal pipe splicing
dma-buf: remove useless FMODE_LSEEK flag
vfio: do not set FMODE_LSEEK flag
.../watchdog/convert_drivers_to_kernel_api.rst | 1 -
arch/parisc/kernel/perf.c | 1 -
arch/powerpc/kernel/eeh.c | 4 ----
arch/powerpc/platforms/52xx/mpc52xx_gpt.c | 1 -
arch/powerpc/platforms/cell/spufs/file.c | 17 -----------------
arch/powerpc/platforms/powernv/eeh-powernv.c | 1 -
arch/powerpc/platforms/pseries/dtl.c | 1 -
arch/s390/hypfs/hypfs_dbfs.c | 1 -
arch/s390/hypfs/inode.c | 1 -
arch/s390/kernel/debug.c | 1 -
arch/s390/kernel/perf_cpum_cf.c | 1 -
arch/s390/kernel/sysinfo.c | 1 -
arch/s390/pci/pci_clp.c | 1 -
arch/um/drivers/harddog_kern.c | 1 -
arch/um/drivers/hostaudio_kern.c | 2 --
arch/x86/kernel/cpu/mce/dev-mcelog.c | 1 -
arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 1 -
drivers/acpi/apei/erst-dbg.c | 1 -
drivers/auxdisplay/charlcd.c | 1 -
drivers/block/mtip32xx/mtip32xx.c | 3 ---
drivers/block/pktcdvd.c | 1 -
drivers/bluetooth/hci_vhci.c | 1 -
drivers/bus/moxtet.c | 2 --
drivers/char/agp/frontend.c | 1 -
drivers/char/applicom.c | 1 -
drivers/char/ds1620.c | 1 -
drivers/char/dtlk.c | 1 -
drivers/char/hpet.c | 1 -
drivers/char/ipmi/ipmi_watchdog.c | 1 -
drivers/char/pc8736x_gpio.c | 1 -
drivers/char/pcmcia/cm4000_cs.c | 1 -
drivers/char/pcmcia/cm4040_cs.c | 1 -
drivers/char/pcmcia/scr24x_cs.c | 1 -
drivers/char/ppdev.c | 1 -
drivers/char/scx200_gpio.c | 1 -
drivers/char/sonypi.c | 1 -
drivers/char/tb0219.c | 1 -
drivers/char/tpm/tpm-dev.c | 1 -
drivers/char/tpm/tpm_vtpm_proxy.c | 1 -
drivers/char/tpm/tpmrm-dev.c | 1 -
drivers/char/virtio_console.c | 1 -
drivers/counter/counter-chrdev.c | 1 -
drivers/dma-buf/dma-buf.c | 1 -
drivers/firewire/core-cdev.c | 1 -
drivers/firmware/efi/capsule-loader.c | 1 -
drivers/firmware/efi/test/efi_test.c | 1 -
drivers/firmware/turris-mox-rwtm.c | 1 -
drivers/gnss/core.c | 1 -
drivers/gpio/gpio-mockup.c | 1 -
drivers/gpio/gpiolib-cdev.c | 1 -
drivers/gpu/drm/drm_file.c | 1 -
drivers/gpu/drm/i915/i915_perf.c | 1 -
drivers/gpu/drm/msm/msm_perf.c | 1 -
drivers/gpu/drm/msm/msm_rd.c | 1 -
drivers/hid/uhid.c | 1 -
drivers/hwmon/asus_atk0110.c | 1 -
drivers/hwmon/fschmd.c | 1 -
drivers/hwmon/w83793.c | 1 -
drivers/hwtracing/coresight/coresight-etb10.c | 1 -
.../hwtracing/coresight/coresight-tmc-core.c | 1 -
drivers/hwtracing/intel_th/msu.c | 1 -
drivers/hwtracing/stm/core.c | 1 -
drivers/i2c/i2c-dev.c | 1 -
drivers/infiniband/core/ucma.c | 1 -
drivers/infiniband/core/user_mad.c | 2 --
drivers/infiniband/core/uverbs_main.c | 4 ----
drivers/infiniband/hw/hfi1/fault.c | 1 -
drivers/infiniband/hw/mlx5/devx.c | 2 --
drivers/input/evdev.c | 1 -
drivers/input/joydev.c | 1 -
drivers/input/keyboard/applespi.c | 1 -
drivers/input/misc/uinput.c | 1 -
drivers/input/serio/userio.c | 1 -
drivers/isdn/capi/capi.c | 1 -
drivers/isdn/mISDN/timerdev.c | 1 -
drivers/leds/uleds.c | 1 -
drivers/macintosh/adb.c | 1 -
drivers/macintosh/smu.c | 1 -
drivers/media/cec/core/cec-api.c | 1 -
drivers/media/mc/mc-devnode.c | 1 -
drivers/media/rc/lirc_dev.c | 1 -
drivers/media/usb/uvc/uvc_debugfs.c | 1 -
drivers/media/v4l2-core/v4l2-dev.c | 1 -
drivers/message/fusion/mptctl.c | 1 -
drivers/misc/lis3lv02d/lis3lv02d.c | 1 -
drivers/misc/mei/main.c | 1 -
drivers/misc/phantom.c | 1 -
drivers/mmc/core/block.c | 1 -
drivers/mtd/ubi/cdev.c | 2 --
drivers/mtd/ubi/debug.c | 1 -
drivers/net/netdevsim/fib.c | 1 -
drivers/net/tap.c | 1 -
drivers/net/tun.c | 1 -
.../wireless/broadcom/brcm80211/brcmfmac/core.c | 1 -
drivers/net/wireless/intel/iwlwifi/mvm/d3.c | 1 -
drivers/pinctrl/pinmux.c | 1 -
drivers/platform/chrome/cros_ec_debugfs.c | 1 -
drivers/platform/chrome/wilco_ec/debugfs.c | 1 -
drivers/platform/chrome/wilco_ec/event.c | 1 -
drivers/platform/chrome/wilco_ec/telemetry.c | 1 -
.../platform/surface/surface_aggregator_cdev.c | 1 -
drivers/platform/surface/surface_dtx.c | 1 -
drivers/pps/pps.c | 1 -
drivers/rtc/dev.c | 1 -
drivers/rtc/rtc-m41t80.c | 1 -
drivers/s390/char/fs3270.c | 1 -
drivers/s390/char/sclp_ctl.c | 1 -
drivers/s390/char/tape_char.c | 1 -
drivers/s390/char/uvdevice.c | 1 -
drivers/s390/char/vmcp.c | 1 -
drivers/s390/char/vmlogrdr.c | 1 -
drivers/s390/char/zcore.c | 2 --
drivers/s390/cio/chsc_sch.c | 1 -
drivers/s390/cio/css.c | 1 -
drivers/s390/crypto/pkey_api.c | 1 -
drivers/s390/crypto/zcrypt_api.c | 1 -
drivers/sbus/char/openprom.c | 1 -
drivers/sbus/char/uctrl.c | 1 -
drivers/scsi/sg.c | 1 -
drivers/spi/spidev.c | 1 -
drivers/staging/pi433/pi433_if.c | 1 -
.../intel/int340x_thermal/acpi_thermal_rel.c | 1 -
drivers/tty/tty_io.c | 3 ---
drivers/usb/gadget/function/f_fs.c | 2 --
drivers/usb/gadget/legacy/inode.c | 2 --
drivers/usb/gadget/legacy/raw_gadget.c | 1 -
drivers/usb/gadget/udc/atmel_usba_udc.c | 1 -
drivers/usb/misc/ftdi-elan.c | 1 -
drivers/usb/misc/ldusb.c | 1 -
drivers/usb/mon/mon_bin.c | 1 -
drivers/usb/mon/mon_stat.c | 1 -
drivers/usb/mon/mon_text.c | 2 --
drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 2 --
drivers/vfio/pci/mlx5/main.c | 2 --
drivers/vfio/vfio.c | 2 +-
drivers/watchdog/acquirewdt.c | 1 -
drivers/watchdog/advantechwdt.c | 1 -
drivers/watchdog/alim1535_wdt.c | 1 -
drivers/watchdog/alim7101_wdt.c | 1 -
drivers/watchdog/ar7_wdt.c | 1 -
drivers/watchdog/at91rm9200_wdt.c | 1 -
drivers/watchdog/ath79_wdt.c | 1 -
drivers/watchdog/cpu5wdt.c | 1 -
drivers/watchdog/cpwd.c | 1 -
drivers/watchdog/eurotechwdt.c | 1 -
drivers/watchdog/gef_wdt.c | 1 -
drivers/watchdog/geodewdt.c | 1 -
drivers/watchdog/ib700wdt.c | 1 -
drivers/watchdog/ibmasr.c | 1 -
drivers/watchdog/indydog.c | 1 -
drivers/watchdog/it8712f_wdt.c | 1 -
drivers/watchdog/m54xx_wdt.c | 1 -
drivers/watchdog/machzwd.c | 1 -
drivers/watchdog/mixcomwd.c | 1 -
drivers/watchdog/mtx-1_wdt.c | 1 -
drivers/watchdog/nv_tco.c | 1 -
drivers/watchdog/pc87413_wdt.c | 1 -
drivers/watchdog/pcwd.c | 2 --
drivers/watchdog/pcwd_pci.c | 2 --
drivers/watchdog/pcwd_usb.c | 2 --
drivers/watchdog/pika_wdt.c | 1 -
drivers/watchdog/rc32434_wdt.c | 1 -
drivers/watchdog/rdc321x_wdt.c | 1 -
drivers/watchdog/riowd.c | 1 -
drivers/watchdog/sa1100_wdt.c | 1 -
drivers/watchdog/sb_wdog.c | 1 -
drivers/watchdog/sbc60xxwdt.c | 1 -
drivers/watchdog/sbc7240_wdt.c | 1 -
drivers/watchdog/sbc8360.c | 1 -
drivers/watchdog/sbc_epx_c3.c | 1 -
drivers/watchdog/sbc_fitpc2_wdt.c | 1 -
drivers/watchdog/sc1200wdt.c | 1 -
drivers/watchdog/sc520_wdt.c | 1 -
drivers/watchdog/sch311x_wdt.c | 1 -
drivers/watchdog/scx200_wdt.c | 1 -
drivers/watchdog/smsc37b787_wdt.c | 1 -
drivers/watchdog/w83877f_wdt.c | 1 -
drivers/watchdog/w83977f_wdt.c | 1 -
drivers/watchdog/wafer5823wdt.c | 1 -
drivers/watchdog/wdrtas.c | 2 --
drivers/watchdog/wdt.c | 2 --
drivers/watchdog/wdt285.c | 1 -
drivers/watchdog/wdt977.c | 1 -
drivers/watchdog/wdt_pci.c | 2 --
drivers/xen/evtchn.c | 1 -
drivers/xen/mcelog.c | 1 -
drivers/xen/xenbus/xenbus_dev_frontend.c | 1 -
fs/debugfs/file.c | 1 -
fs/dlm/debug_fs.c | 1 -
fs/efivarfs/file.c | 1 -
fs/file_table.c | 2 ++
fs/fsopen.c | 1 -
fs/fuse/control.c | 4 ----
fs/fuse/dev.c | 1 -
fs/ksmbd/vfs.c | 4 ++--
fs/nsfs.c | 1 -
fs/open.c | 2 ++
fs/pipe.c | 1 -
fs/splice.c | 10 ++++------
fs/ubifs/debug.c | 2 --
include/linux/debugfs.h | 1 -
kernel/bpf/bpf_iter.c | 1 -
kernel/events/core.c | 1 -
kernel/power/user.c | 1 -
kernel/relay.c | 1 -
kernel/time/posix-clock.c | 1 -
kernel/trace/trace.c | 3 ---
mm/huge_memory.c | 1 -
net/mac80211/rc80211_minstrel_ht_debugfs.c | 2 --
net/rfkill/core.c | 1 -
net/socket.c | 1 -
net/sunrpc/cache.c | 4 ----
net/sunrpc/rpc_pipe.c | 1 -
scripts/coccinelle/api/stream_open.cocci | 1 -
sound/core/control.c | 1 -
sound/core/oss/mixer_oss.c | 1 -
sound/core/oss/pcm_oss.c | 1 -
sound/core/pcm_native.c | 2 --
sound/core/rawmidi.c | 1 -
sound/core/seq/seq_clientmgr.c | 1 -
sound/core/timer.c | 1 -
sound/oss/dmasound/dmasound_core.c | 3 ---
virt/kvm/kvm_main.c | 1 -
223 files changed, 11 insertions(+), 283 deletions(-)
--
2.35.1