From: Kees Cook Date: Tue, 15 Apr 2025 23:14:24 +0000 (-0700) Subject: mod_devicetable: Enlarge the maximum platform_device_id name length X-Git-Tag: v6.16-rc1~151^2~17 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=655862865c97ff55e4f3f2aaa7708f42f0ea3bd8;p=thirdparty%2Fkernel%2Flinux.git mod_devicetable: Enlarge the maximum platform_device_id name length The 20 byte length of struct platform_device_id::name is not long enough for many devices (especially regulators), where the string initialization is getting truncated and missing the trailing NUL byte. This is seen with GCC 15's -Wunterminated-string-initialization option: drivers/regulator/hi6421v530-regulator.c:189:19: warning: initializer-string for array of 'char' truncates NUL terminator but destination lacks 'nonstring' attribute (21 chars into 20 available) [-Wunterminated-string-initialization] 189 | { .name = "hi6421v530-regulator" }, | ^~~~~~~~~~~~~~~~~~~~~~ drivers/regulator/hi6421v600-regulator.c:278:19: warning: initializer-string for array of 'char' truncates NUL terminator but destination lacks 'nonstring' attribute (21 chars into 20 available) [-Wunterminated-string-initialization] 278 | { .name = "hi6421v600-regulator" }, | ^~~~~~~~~~~~~~~~~~~~~~ drivers/regulator/lp87565-regulator.c:233:11: warning: initializer-string for array of 'char' truncates NUL terminator but destination lacks 'nonstring' attribute (21 chars into 20 available) [-Wunterminated-string-initialization] 233 | { "lp87565-q1-regulator", }, | ^~~~~~~~~~~~~~~~~~~~~~ sound/soc/fsl/imx-pcm-rpmsg.c:818:19: warning: initializer-string for array of 'char' truncates NUL terminator but destination lacks 'nonstring' attribute (21 chars into 20 available) [-Wunterminated-string-initialization] 818 | { .name = "rpmsg-micfil-channel" }, | ^~~~~~~~~~~~~~~~~~~~~~ drivers/iio/light/hid-sensor-als.c:457:25: warning: initializer-string for array of 'char' truncates NUL terminator but destination lacks 'nonstring' attribute (21 chars into 20 available) [-Wunterminated-string-initialization] 457 | .name = "HID-SENSOR-LISS-0041", | ^~~~~~~~~~~~~~~~~~~~~~ drivers/iio/light/hid-sensor-prox.c:366:25: warning: initializer-string for array of 'char' truncates NUL terminator but destination lacks 'nonstring' attribute (21 chars into 20 available) [-Wunterminated-string-initialization] 366 | .name = "HID-SENSOR-LISS-0226", | ^~~~~~~~~~~~~~~~~~~~~~ Increase the length to 24, slightly more than is currently being used by the affected drivers. The string is used in '%s' format strings and via the module code, which appears to do its own length encoding. This size was chosen because there was already a 4 byte hole in the structure: struct platform_device_id { char name[20]; /* 0 20 */ /* XXX 4 bytes hole, try to pack */ kernel_ulong_t driver_data; /* 24 8 */ /* size: 32, cachelines: 1, members: 2 */ /* sum members: 28, holes: 1, sum holes: 4 */ /* last cacheline: 32 bytes */ }; Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20250415231420.work.066-kees@kernel.org Signed-off-by: Kees Cook --- diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index bd7e60c0b72f0..ebcee9328168b 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -601,7 +601,7 @@ struct dmi_system_id { #define DMI_MATCH(a, b) { .slot = a, .substr = b } #define DMI_EXACT_MATCH(a, b) { .slot = a, .substr = b, .exact_match = 1 } -#define PLATFORM_NAME_SIZE 20 +#define PLATFORM_NAME_SIZE 24 #define PLATFORM_MODULE_PREFIX "platform:" struct platform_device_id {