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author | Justin Stitt <justinstitt@google.com> | 2023-09-13 17:13:04 +0000 |
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committer | Corey Minyard <minyard@acm.org> | 2023-09-13 12:55:11 -0500 |
commit | b00839ca4cca8aa9641c121c848a553d6220ce70 (patch) | |
tree | 58a37095c9ccf41799e3d9880cccc8eec73644fb /drivers/char | |
parent | 3669558bdf354cd352be955ef2764cde6a9bf5ec (diff) | |
download | linux-b00839ca4cca8aa9641c121c848a553d6220ce70.tar.gz linux-b00839ca4cca8aa9641c121c848a553d6220ce70.tar.bz2 linux-b00839ca4cca8aa9641c121c848a553d6220ce70.zip |
ipmi: refactor deprecated strncpy
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
In this case, strncpy is being used specifically for its NUL-padding
behavior (and has been commented as such). Moreover, the destination
string is not required to be NUL-terminated [2].
We can use a more robust and less ambiguous interface in
`memcpy_and_pad` which makes the code more readable and even eliminates
the need for that comment.
Let's also use `strnlen` instead of `strlen()` with an upper-bounds
check as this is intrinsically a part of `strnlen`.
Also included in this patch is a simple 1:1 change of `strncpy` to
`strscpy` for ipmi_ssif.c. If NUL-padding is wanted here as well then we
should opt again for `strscpy_pad`.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://lore.kernel.org/all/ZQEADYBl0uZ1nX60@mail.minyard.net/ [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Message-Id: <20230913-strncpy-drivers-char-ipmi-ipmi-v2-1-e3bc0f6e599f@google.com>
Signed-off-by: Corey Minyard <minyard@acm.org>
Diffstat (limited to 'drivers/char')
-rw-r--r-- | drivers/char/ipmi/ipmi_msghandler.c | 11 | ||||
-rw-r--r-- | drivers/char/ipmi/ipmi_ssif.c | 2 |
2 files changed, 4 insertions, 9 deletions
diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index 186f1fee7534..d6f14279684d 100644 --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -5377,20 +5377,15 @@ static void send_panic_events(struct ipmi_smi *intf, char *str) j = 0; while (*p) { - int size = strlen(p); + int size = strnlen(p, 11); - if (size > 11) - size = 11; data[0] = 0; data[1] = 0; data[2] = 0xf0; /* OEM event without timestamp. */ data[3] = intf->addrinfo[0].address; data[4] = j++; /* sequence # */ - /* - * Always give 11 bytes, so strncpy will fill - * it with zeroes for me. - */ - strncpy(data+5, p, 11); + + memcpy_and_pad(data+5, 11, p, size, '\0'); p += size; ipmi_panic_request_and_wait(intf, &addr, &msg); diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c index df8dd50b4cbe..1f7600c361e6 100644 --- a/drivers/char/ipmi/ipmi_ssif.c +++ b/drivers/char/ipmi/ipmi_ssif.c @@ -1945,7 +1945,7 @@ static int new_ssif_client(int addr, char *adapter_name, } } - strncpy(addr_info->binfo.type, DEVICE_NAME, + strscpy(addr_info->binfo.type, DEVICE_NAME, sizeof(addr_info->binfo.type)); addr_info->binfo.addr = addr; addr_info->binfo.platform_data = addr_info; |