Packed structures like struct uuid are not aligned. GCC 9.1 therefore throws an error when trying to compile gen_rand_uuid().
lib/uuid.c: In function ‘gen_rand_uuid’: lib/uuid.c:244:2: error: converting a packed ‘struct uuid’ pointer (alignment 1) to a ‘unsigned int’ pointer (alignment 4) may result in an unaligned pointer value [-Werror=address-of-packed-member] 244 | unsigned int *ptr = (unsigned int *)&uuid; | ^~~~~~~~
Generate the uuid in a properly aligned buffer.
The byte order of a random number should not matter. Do not call cpu_to_be32() to change the byte order.
Reported-by: Ramon Fried rfried.dev@gmail.com Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de --- lib/uuid.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/lib/uuid.c b/lib/uuid.c index 7d7a2749b6..c18014171c 100644 --- a/lib/uuid.c +++ b/lib/uuid.c @@ -240,25 +240,25 @@ void uuid_bin_to_str(unsigned char *uuid_bin, char *uuid_str, int str_format) #if defined(CONFIG_RANDOM_UUID) || defined(CONFIG_CMD_UUID) void gen_rand_uuid(unsigned char *uuid_bin) { - struct uuid uuid; - unsigned int *ptr = (unsigned int *)&uuid; + u32 ptr[4]; + struct uuid *uuid = (struct uuid *)ptr; int i;
srand(get_ticks() + rand());
/* Set all fields randomly */ - for (i = 0; i < sizeof(struct uuid) / sizeof(*ptr); i++) - *(ptr + i) = cpu_to_be32(rand()); + for (i = 0; i < 4; i++) + ptr[i] = rand();
- clrsetbits_be16(&uuid.time_hi_and_version, + clrsetbits_be16(&uuid->time_hi_and_version, UUID_VERSION_MASK, UUID_VERSION << UUID_VERSION_SHIFT);
- clrsetbits_8(&uuid.clock_seq_hi_and_reserved, + clrsetbits_8(&uuid->clock_seq_hi_and_reserved, UUID_VARIANT_MASK, UUID_VARIANT << UUID_VARIANT_SHIFT);
- memcpy(uuid_bin, &uuid, sizeof(struct uuid)); + memcpy(uuid_bin, uuid, 16); }
/* -- 2.22.0