diff options
author | Justin Stitt <justinstitt@google.com> | 2023-09-25 06:54:51 +0000 |
---|---|---|
committer | Mike Snitzer <snitzer@kernel.org> | 2023-10-23 13:02:37 -0400 |
commit | 0ffb645ea821fbad4215b6a5681b823639c24660 (patch) | |
tree | ee407dcd13abcedd3e4f3b79e7a473fc3a3fd261 | |
parent | e9d7bd2c8664aa43866c7985d9050a052516c07d (diff) |
dm ioctl: replace deprecated strncpy with strscpy_pad
`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.
We expect `spec->target_type` to be NUL-terminated based on its use with
a format string after `dm_table_add_target()` is called
| r = dm_table_add_target(table, spec->target_type,
| (sector_t) spec->sector_start,
| (sector_t) spec->length,
| target_params);
... wherein `spec->target_type` is passed as parameter `type` and later
printed with DMERR:
| DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
It appears that `spec` is not zero-allocated and thus NUL-padding may be
required in this ioctl context.
Considering the above, a suitable replacement is `strscpy_pad` due to
the fact that it guarantees NUL-termination whilst maintaining the
NUL-padding behavior that strncpy provides.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://github.com/KSPP/linux/issues/90
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
-rw-r--r-- | drivers/md/dm-ioctl.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 21ebb6c39394..e65058e0ed06 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -1295,8 +1295,8 @@ static void retrieve_status(struct dm_table *table, spec->status = 0; spec->sector_start = ti->begin; spec->length = ti->len; - strncpy(spec->target_type, ti->type->name, - sizeof(spec->target_type) - 1); + strscpy_pad(spec->target_type, ti->type->name, + sizeof(spec->target_type)); outptr += sizeof(struct dm_target_spec); remaining = len - (outptr - outbuf); |