[PATCH v3 0/4] floppy: suppress UBSAN warning in setup_rw_floppy()

From: Denis Efremov
Date: Fri May 01 2020 - 09:46:16 EST


These patches are based on Willy's cleanup patches
https://lkml.org/lkml/2020/3/31/609.

The first patch removes pr_cont() in setup_DMA() and prints the contents of
cmd buffer with print_hex_dump(). The last patch also touches these lines
and changes cmd buffer to fullcmd. The 2,3 patches introduce defines to
make it more clear why cmd_count in struct floppy_raw_cmd allows
out-of-bounds access for cmd, reply_count, reply fields. Last patch
handles the warning.

There is the checkpatch warning because of the line length 81 > 80 in
the definition of valid_floppy_drive_params(). This function
intentionally uses autodetect[8] as argument to highlight that this
is exactly the autodetect field from structs floppy_drive_params and
compat_floppy_drive_params. I think that this warning is not a big
problem since next function definition is 85 chars long and whole
driver requires "restyling".

Changes in v3:
- fix indentation in the second patch
- remove FD_RAW_REPLY_SIZE from print_hex_dump() in the third patch

Changes in v2:
- add FD_RAW_CMD_FULLSIZE to the second patch
- add union with fullcmd to struct floppy_raw_cmd in the last patch

Denis Efremov (4):
floppy: use print_hex_dump() in setup_DMA()
floppy: add FD_AUTODETECT_SIZE define for struct floppy_drive_params
floppy: add defines for sizes of cmd & reply buffers of floppy_raw_cmd
floppy: suppress UBSAN warning in setup_rw_floppy()

drivers/block/floppy.c | 39 ++++++++++++++-------------------------
include/uapi/linux/fd.h | 26 ++++++++++++++++++++++----
2 files changed, 36 insertions(+), 29 deletions(-)

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2.25.3