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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
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Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
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+Code Examples
+=============
+
+Code Example For Symmetric Key Cipher Operation
+-----------------------------------------------
+
+This code encrypts some data with AES-256-XTS. For sake of example,
+all inputs are random bytes, the encryption is done in-place, and it's
+assumed the code is running in a context where it can sleep.
+
+::
+
+ static int test_skcipher(void)
+ {
+ struct crypto_skcipher *tfm = NULL;
+ struct skcipher_request *req = NULL;
+ u8 *data = NULL;
+ const size_t datasize = 512; /* data size in bytes */
+ struct scatterlist sg;
+ DECLARE_CRYPTO_WAIT(wait);
+ u8 iv[16]; /* AES-256-XTS takes a 16-byte IV */
+ u8 key[64]; /* AES-256-XTS takes a 64-byte key */
+ int err;
+
+ /*
+ * Allocate a tfm (a transformation object) and set the key.
+ *
+ * In real-world use, a tfm and key are typically used for many
+ * encryption/decryption operations. But in this example, we'll just do a
+ * single encryption operation with it (which is not very efficient).
+ */
+
+ tfm = crypto_alloc_skcipher("xts(aes)", 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_err("Error allocating xts(aes) handle: %ld\n", PTR_ERR(tfm));
+ return PTR_ERR(tfm);
+ }
+
+ get_random_bytes(key, sizeof(key));
+ err = crypto_skcipher_setkey(tfm, key, sizeof(key));
+ if (err) {
+ pr_err("Error setting key: %d\n", err);
+ goto out;
+ }
+
+ /* Allocate a request object */
+ req = skcipher_request_alloc(tfm, GFP_KERNEL);
+ if (!req) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ /* Prepare the input data */
+ data = kmalloc(datasize, GFP_KERNEL);
+ if (!data) {
+ err = -ENOMEM;
+ goto out;
+ }
+ get_random_bytes(data, datasize);
+
+ /* Initialize the IV */
+ get_random_bytes(iv, sizeof(iv));
+
+ /*
+ * Encrypt the data in-place.
+ *
+ * For simplicity, in this example we wait for the request to complete
+ * before proceeding, even if the underlying implementation is asynchronous.
+ *
+ * To decrypt instead of encrypt, just change crypto_skcipher_encrypt() to
+ * crypto_skcipher_decrypt().
+ */
+ sg_init_one(&sg, data, datasize);
+ skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
+ CRYPTO_TFM_REQ_MAY_SLEEP,
+ crypto_req_done, &wait);
+ skcipher_request_set_crypt(req, &sg, &sg, datasize, iv);
+ err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
+ if (err) {
+ pr_err("Error encrypting data: %d\n", err);
+ goto out;
+ }
+
+ pr_debug("Encryption was successful\n");
+ out:
+ crypto_free_skcipher(tfm);
+ skcipher_request_free(req);
+ kfree(data);
+ return err;
+ }
+
+
+Code Example For Use of Operational State Memory With SHASH
+-----------------------------------------------------------
+
+::
+
+
+ struct sdesc {
+ struct shash_desc shash;
+ char ctx[];
+ };
+
+ static struct sdesc *init_sdesc(struct crypto_shash *alg)
+ {
+ struct sdesc *sdesc;
+ int size;
+
+ size = sizeof(struct shash_desc) + crypto_shash_descsize(alg);
+ sdesc = kmalloc(size, GFP_KERNEL);
+ if (!sdesc)
+ return ERR_PTR(-ENOMEM);
+ sdesc->shash.tfm = alg;
+ return sdesc;
+ }
+
+ static int calc_hash(struct crypto_shash *alg,
+ const unsigned char *data, unsigned int datalen,
+ unsigned char *digest)
+ {
+ struct sdesc *sdesc;
+ int ret;
+
+ sdesc = init_sdesc(alg);
+ if (IS_ERR(sdesc)) {
+ pr_info("can't alloc sdesc\n");
+ return PTR_ERR(sdesc);
+ }
+
+ ret = crypto_shash_digest(&sdesc->shash, data, datalen, digest);
+ kfree(sdesc);
+ return ret;
+ }
+
+ static int test_hash(const unsigned char *data, unsigned int datalen,
+ unsigned char *digest)
+ {
+ struct crypto_shash *alg;
+ char *hash_alg_name = "sha1-padlock-nano";
+ int ret;
+
+ alg = crypto_alloc_shash(hash_alg_name, 0, 0);
+ if (IS_ERR(alg)) {
+ pr_info("can't alloc alg %s\n", hash_alg_name);
+ return PTR_ERR(alg);
+ }
+ ret = calc_hash(alg, data, datalen, digest);
+ crypto_free_shash(alg);
+ return ret;
+ }
+
+
+Code Example For Random Number Generator Usage
+----------------------------------------------
+
+::
+
+
+ static int get_random_numbers(u8 *buf, unsigned int len)
+ {
+ struct crypto_rng *rng = NULL;
+ char *drbg = "stdrng";
+ int ret;
+
+ if (!buf || !len) {
+ pr_debug("No output buffer provided\n");
+ return -EINVAL;
+ }
+
+ rng = crypto_alloc_rng(drbg, 0, 0);
+ if (IS_ERR(rng)) {
+ pr_debug("could not allocate RNG handle for %s\n", drbg);
+ return PTR_ERR(rng);
+ }
+
+ ret = crypto_rng_get_bytes(rng, buf, len);
+ if (ret < 0)
+ pr_debug("generation of random numbers failed\n");
+ else if (ret == 0)
+ pr_debug("RNG returned no data");
+ else
+ pr_debug("RNG returned %d bytes of data\n", ret);
+
+ out:
+ crypto_free_rng(rng);
+ return ret;
+ }