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| author | Justin Stitt <justinstitt@google.com> | 2023-08-11 19:33:51 +0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2023-08-16 17:50:55 +0300 |
| commit | d232606773a0b09ec7f1ffc25f63abe801d011fd (patch) | |
| tree | 4acee58567032dbe83d5ff4df70e13cb1460aac7 /arch/arm64/kernel/idreg-override.c | |
| parent | 18b8f57a7f51b4c834e5e974ec38133c02e9eb58 (diff) | |
| download | linux-d232606773a0b09ec7f1ffc25f63abe801d011fd.tar.xz | |
arm64/sysreg: refactor deprecated strncpy
`strncpy` is deprecated for use on NUL-terminated destination strings
[1]. Which seems to be the case here due to the forceful setting of `buf`'s
tail to 0.
A suitable replacement is `strscpy` [2] due to the fact that it
guarantees NUL-termination on its destination buffer argument which is
_not_ the case for `strncpy`!
In this case, we can simplify the logic and also check for any silent
truncation by using `strscpy`'s return value.
This should have no functional change and yet uses a more robust and
less ambiguous interface whilst reducing code complexity.
Link: www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings[1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Suggested-by: Kees Cook <keescook@chromium.org>
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20230811-strncpy-arch-arm64-v2-1-ba84eabffadb@google.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/kernel/idreg-override.c')
| -rw-r--r-- | arch/arm64/kernel/idreg-override.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c index 2fe2491b692c..aee12c75b738 100644 --- a/arch/arm64/kernel/idreg-override.c +++ b/arch/arm64/kernel/idreg-override.c @@ -262,9 +262,9 @@ static __init void __parse_cmdline(const char *cmdline, bool parse_aliases) if (!len) return; - len = min(len, ARRAY_SIZE(buf) - 1); - strncpy(buf, cmdline, len); - buf[len] = 0; + len = strscpy(buf, cmdline, ARRAY_SIZE(buf)); + if (len == -E2BIG) + len = ARRAY_SIZE(buf) - 1; if (strcmp(buf, "--") == 0) return; |