mirror of https://github.com/torvalds/linux.git
The `insn_rw_emulate_bits()` function is used as a default handler for
`INSN_READ` instructions for subdevices that have a handler for
`INSN_BITS` but not for `INSN_READ`. Similarly, it is used as a default
handler for `INSN_WRITE` instructions for subdevices that have a handler
for `INSN_BITS` but not for `INSN_WRITE`. It works by emulating the
`INSN_READ` or `INSN_WRITE` instruction handling with a constructed
`INSN_BITS` instruction. However, `INSN_READ` and `INSN_WRITE`
instructions are supposed to be able read or write multiple samples,
indicated by the `insn->n` value, but `insn_rw_emulate_bits()` currently
only handles a single sample. For `INSN_READ`, the comedi core will
copy `insn->n` samples back to user-space. (That triggered KASAN
kernel-infoleak errors when `insn->n` was greater than 1, but that is
being fixed more generally elsewhere in the comedi core.)
Make `insn_rw_emulate_bits()` either handle `insn->n` samples, or return
an error, to conform to the general expectation for `INSN_READ` and
`INSN_WRITE` handlers.
Fixes:
|
||
|---|---|---|
| .. | ||
| drivers | ||
| kcomedilib | ||
| Kconfig | ||
| Makefile | ||
| TODO | ||
| comedi_buf.c | ||
| comedi_fops.c | ||
| comedi_internal.h | ||
| comedi_pci.c | ||
| comedi_pcmcia.c | ||
| comedi_usb.c | ||
| drivers.c | ||
| proc.c | ||
| range.c | ||