diff options
author | Justin Stitt <justinstitt@google.com> | 2023-09-19 05:30:35 +0000 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2023-10-03 18:23:02 -0600 |
commit | e1f2760ba3478fa3f8c48db8e91fbe3df8bea2f8 (patch) | |
tree | 14e57e3e8031ce4eec867b5a9619ec39987626ba /drivers/regulator/rk808-regulator.c | |
parent | 114b0ff62a6510eb218660cb4925b4c4a01cdd84 (diff) |
null_blk: replace strncpy with strscpy
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We should favor a more robust and less ambiguous interface.
We expect that both `nullb->disk_name` and `disk->disk_name` be
NUL-terminated:
| snprintf(nullb->disk_name, sizeof(nullb->disk_name),
| "%s", config_item_name(&dev->group.cg_item));
...
| pr_info("disk %s created\n", nullb->disk_name);
It seems like NUL-padding may be required due to __assign_disk_name()
utilizing a memcpy as opposed to a `str*cpy` api.
| static inline void __assign_disk_name(char *name, struct gendisk *disk)
| {
| if (disk)
| memcpy(name, disk->disk_name, DISK_NAME_LEN);
| else
| memset(name, 0, DISK_NAME_LEN);
| }
Then we go and print it with `__print_disk_name` which wraps `nullb_trace_disk_name()`.
| #define __print_disk_name(name) nullb_trace_disk_name(p, name)
This function obviously expects a NUL-terminated string.
| const char *nullb_trace_disk_name(struct trace_seq *p, char *name)
| {
| const char *ret = trace_seq_buffer_ptr(p);
|
| if (name && *name)
| trace_seq_printf(p, "disk=%s, ", name);
| trace_seq_putc(p, 0);
|
| return ret;
| }
>From the above, we need both 1) a NUL-terminated string and 2) a
NUL-padded string. So, let's use strscpy_pad() as per Kees' suggestion
from v1.
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
Cc: linux-hardening@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230919-strncpy-drivers-block-null_blk-main-c-v3-1-10cf0a87a2c3@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/regulator/rk808-regulator.c')
0 files changed, 0 insertions, 0 deletions