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`strncpy` is deprecated for use on NUL-terminated destination strings [1]. A suitable replacement is `strscpy` [2] due to the fact that it guarantees NUL-termination on its destination buffer argument which is _not_ always the case for `strncpy`! It should be noted that, in this case, the destination buffer has a length strictly greater than the source string. Moreover, the source string is NUL-terminated (and so is the destination) which means there was no real bug happening here. Nonetheless, this patch would get us one step closer to eliminating the `strncpy` API in the kernel, as its use is too ambiguous. We need to favor less ambiguous replacements such as: strscpy, strscpy_pad, strtomem and strtomem_pad (amongst others). Technically, my patch yields subtly different behavior. The original implementation with `strncpy` would fill the entire destination buffer with null bytes [3] while `strscpy` will leave the junk, uninitialized bytes trailing after the _mandatory_ NUL-termination. So, if somehow `card->driver` or `card->shortname` require this NUL-padding behavior then `strscpy_pad` should be used. My interpretation, though, is that the aforementioned fields are just fine as NUL-terminated strings. Please correct my assumptions if needed and I'll send in a v2. [1]: www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [2]: manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [3]: https://linux.die.net/man/3/strncpy Link: https://github.com/KSPP/linux/issues/90 Link: https://lore.kernel.org/r/20230727-sound-xen-v1-1-89dd161351f1@google.com (related ALSA patch) Signed-off-by: Justin Stitt <justinstitt@google.com> Link: https://lore.kernel.org/r/20230727-sound-usb-bcd2000-v1-1-0dc73684b2f0@google.com Signed-off-by: Takashi Iwai <tiwai@suse.de> |
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| .. | ||
| 6fire | ||
| bcd2000 | ||
| caiaq | ||
| hiface | ||
| line6 | ||
| misc | ||
| usx2y | ||
| card.c | ||
| card.h | ||
| clock.c | ||
| clock.h | ||
| endpoint.c | ||
| endpoint.h | ||
| format.c | ||
| format.h | ||
| helper.c | ||
| helper.h | ||
| implicit.c | ||
| implicit.h | ||
| Kconfig | ||
| Makefile | ||
| media.c | ||
| media.h | ||
| midi.c | ||
| midi.h | ||
| midi2.c | ||
| midi2.h | ||
| mixer_maps.c | ||
| mixer_quirks.c | ||
| mixer_quirks.h | ||
| mixer_s1810c.c | ||
| mixer_s1810c.h | ||
| mixer_scarlett_gen2.c | ||
| mixer_scarlett_gen2.h | ||
| mixer_scarlett.c | ||
| mixer_scarlett.h | ||
| mixer_us16x08.c | ||
| mixer_us16x08.h | ||
| mixer.c | ||
| mixer.h | ||
| pcm.c | ||
| pcm.h | ||
| power.c | ||
| power.h | ||
| proc.c | ||
| proc.h | ||
| quirks-table.h | ||
| quirks.c | ||
| quirks.h | ||
| stream.c | ||
| stream.h | ||
| usbaudio.h | ||
| validate.c | ||