Fix gcc uninitialized warning in FreeBSD zio_crypt.c
With gcc we are seeing the following -Werror warning:
In file included from /workspace/src/sys/contrib/openzfs/include/os/freebsd/spl/sys/sunddi.h:28, from /workspace/src/sys/contrib/openzfs/include/sys/zfs_context.h:69: In function 'zfs_uio_init', inlined from 'zio_do_crypt_data' at /workspace/src/sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c:1690:2: /workspace/src/sys/contrib/openzfs/include/os/freebsd/spl/sys/uio.h:102:45: error: 'puio_s.uio_offset' is used uninitialized [-Werror=uninitialized] 102 | zfs_uio_soffset(uio) = uio_s->uio_offset; | ~~~~~^~~~~~~~~~~~ /workspace/src/sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c: In function 'zio_do_crypt_data': /workspace/src/sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c:1683:20: note: 'puio_s' declared here 1683 | struct uio puio_s, cuio_s; | ^~~~~~ In function 'zfs_uio_init', inlined from 'zio_do_crypt_data' at /workspace/src/sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c:1691:2: /workspace/src/sys/contrib/openzfs/include/os/freebsd/spl/sys/uio.h:102:45: error: 'cuio_s.uio_offset' is used uninitialized [-Werror=uninitialized] 102 | zfs_uio_soffset(uio) = uio_s->uio_offset; | ~~~~~^~~~~~~~~~~~ /workspace/src/sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c: In function 'zio_do_crypt_data': /workspace/src/sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c:1683:28: note: 'cuio_s' declared here 1683 | struct uio puio_s, cuio_s; | ^~~~~~
Indeed, zfs_uio_init() does:
static __inline void zfs_uio_init(zfs_uio_t *uio, struct uio *uio_s) { memset(uio, 0, sizeof (zfs_uio_t)); if (uio_s != NULL) { GET_UIO_STRUCT(uio) = uio_s; zfs_uio_soffset(uio) = uio_s->uio_offset; } }
while the code in zio_crypt.c has:
/* * Primary encryption / decryption entrypoint for zio data. */ int zio_do_crypt_data(boolean_t encrypt, zio_crypt_key_t *key, dmu_object_type_t ot, boolean_t byteswap, uint8_t *salt, uint8_t *iv, uint8_t *mac, uint_t datalen, uint8_t *plainbuf, uint8_t *cipherbuf, boolean_t *no_crypt) { int ret; boolean_t locked = B_FALSE; uint64_t crypt = key->zk_crypt; uint_t keydata_len = zio_crypt_table[crypt].ci_keylen; uint_t enc_len, auth_len; zfs_uio_t puio, cuio; struct uio puio_s, cuio_s; uint8_t enc_keydata[MASTER_KEY_MAX_LEN]; crypto_key_t tmp_ckey, *ckey = NULL; freebsd_crypt_session_t *tmpl = NULL; uint8_t *authbuf = NULL; zfs_uio_init(&puio, &puio_s); zfs_uio_init(&cuio, &cuio_s); memset(GET_UIO_STRUCT(&puio), 0, sizeof (struct uio)); memset(GET_UIO_STRUCT(&cuio), 0, sizeof (struct uio));
So between the declaration of puio_s and cuio_s, there is no
initialization of these variables before zfs_uio_init() gets called.
Similar to the Linux variant of zio_crypt.c, I think it would be better
to memset the structs puio_s and cuis_s _before_ calling
zfs_uio_init().
Reviewed by: tsoome
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D47281
(cherry picked from commit 3ceba58a7509418b47b8fca2d2b6bbf088714e26)