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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /crypto/ctr.c
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
Diffstat (limited to 'crypto/ctr.c')
-rw-r--r--crypto/ctr.c360
1 files changed, 360 insertions, 0 deletions
diff --git a/crypto/ctr.c b/crypto/ctr.c
new file mode 100644
index 000000000..a388f0ceb
--- /dev/null
+++ b/crypto/ctr.c
@@ -0,0 +1,360 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * CTR: Counter mode
+ *
+ * (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
+ */
+
+#include <crypto/algapi.h>
+#include <crypto/ctr.h>
+#include <crypto/internal/cipher.h>
+#include <crypto/internal/skcipher.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+struct crypto_rfc3686_ctx {
+ struct crypto_skcipher *child;
+ u8 nonce[CTR_RFC3686_NONCE_SIZE];
+};
+
+struct crypto_rfc3686_req_ctx {
+ u8 iv[CTR_RFC3686_BLOCK_SIZE];
+ struct skcipher_request subreq CRYPTO_MINALIGN_ATTR;
+};
+
+static void crypto_ctr_crypt_final(struct skcipher_walk *walk,
+ struct crypto_cipher *tfm)
+{
+ unsigned int bsize = crypto_cipher_blocksize(tfm);
+ unsigned long alignmask = crypto_cipher_alignmask(tfm);
+ u8 *ctrblk = walk->iv;
+ u8 tmp[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
+ u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1);
+ const u8 *src = walk->src.virt.addr;
+ u8 *dst = walk->dst.virt.addr;
+ unsigned int nbytes = walk->nbytes;
+
+ crypto_cipher_encrypt_one(tfm, keystream, ctrblk);
+ crypto_xor_cpy(dst, keystream, src, nbytes);
+
+ crypto_inc(ctrblk, bsize);
+}
+
+static int crypto_ctr_crypt_segment(struct skcipher_walk *walk,
+ struct crypto_cipher *tfm)
+{
+ void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
+ crypto_cipher_alg(tfm)->cia_encrypt;
+ unsigned int bsize = crypto_cipher_blocksize(tfm);
+ u8 *ctrblk = walk->iv;
+ const u8 *src = walk->src.virt.addr;
+ u8 *dst = walk->dst.virt.addr;
+ unsigned int nbytes = walk->nbytes;
+
+ do {
+ /* create keystream */
+ fn(crypto_cipher_tfm(tfm), dst, ctrblk);
+ crypto_xor(dst, src, bsize);
+
+ /* increment counter in counterblock */
+ crypto_inc(ctrblk, bsize);
+
+ src += bsize;
+ dst += bsize;
+ } while ((nbytes -= bsize) >= bsize);
+
+ return nbytes;
+}
+
+static int crypto_ctr_crypt_inplace(struct skcipher_walk *walk,
+ struct crypto_cipher *tfm)
+{
+ void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
+ crypto_cipher_alg(tfm)->cia_encrypt;
+ unsigned int bsize = crypto_cipher_blocksize(tfm);
+ unsigned long alignmask = crypto_cipher_alignmask(tfm);
+ unsigned int nbytes = walk->nbytes;
+ u8 *dst = walk->dst.virt.addr;
+ u8 *ctrblk = walk->iv;
+ u8 tmp[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
+ u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1);
+
+ do {
+ /* create keystream */
+ fn(crypto_cipher_tfm(tfm), keystream, ctrblk);
+ crypto_xor(dst, keystream, bsize);
+
+ /* increment counter in counterblock */
+ crypto_inc(ctrblk, bsize);
+
+ dst += bsize;
+ } while ((nbytes -= bsize) >= bsize);
+
+ return nbytes;
+}
+
+static int crypto_ctr_crypt(struct skcipher_request *req)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
+ const unsigned int bsize = crypto_cipher_blocksize(cipher);
+ struct skcipher_walk walk;
+ unsigned int nbytes;
+ int err;
+
+ err = skcipher_walk_virt(&walk, req, false);
+
+ while (walk.nbytes >= bsize) {
+ if (walk.src.virt.addr == walk.dst.virt.addr)
+ nbytes = crypto_ctr_crypt_inplace(&walk, cipher);
+ else
+ nbytes = crypto_ctr_crypt_segment(&walk, cipher);
+
+ err = skcipher_walk_done(&walk, nbytes);
+ }
+
+ if (walk.nbytes) {
+ crypto_ctr_crypt_final(&walk, cipher);
+ err = skcipher_walk_done(&walk, 0);
+ }
+
+ return err;
+}
+
+static int crypto_ctr_create(struct crypto_template *tmpl, struct rtattr **tb)
+{
+ struct skcipher_instance *inst;
+ struct crypto_alg *alg;
+ int err;
+
+ inst = skcipher_alloc_instance_simple(tmpl, tb);
+ if (IS_ERR(inst))
+ return PTR_ERR(inst);
+
+ alg = skcipher_ialg_simple(inst);
+
+ /* Block size must be >= 4 bytes. */
+ err = -EINVAL;
+ if (alg->cra_blocksize < 4)
+ goto out_free_inst;
+
+ /* If this is false we'd fail the alignment of crypto_inc. */
+ if (alg->cra_blocksize % 4)
+ goto out_free_inst;
+
+ /* CTR mode is a stream cipher. */
+ inst->alg.base.cra_blocksize = 1;
+
+ /*
+ * To simplify the implementation, configure the skcipher walk to only
+ * give a partial block at the very end, never earlier.
+ */
+ inst->alg.chunksize = alg->cra_blocksize;
+
+ inst->alg.encrypt = crypto_ctr_crypt;
+ inst->alg.decrypt = crypto_ctr_crypt;
+
+ err = skcipher_register_instance(tmpl, inst);
+ if (err) {
+out_free_inst:
+ inst->free(inst);
+ }
+
+ return err;
+}
+
+static int crypto_rfc3686_setkey(struct crypto_skcipher *parent,
+ const u8 *key, unsigned int keylen)
+{
+ struct crypto_rfc3686_ctx *ctx = crypto_skcipher_ctx(parent);
+ struct crypto_skcipher *child = ctx->child;
+
+ /* the nonce is stored in bytes at end of key */
+ if (keylen < CTR_RFC3686_NONCE_SIZE)
+ return -EINVAL;
+
+ memcpy(ctx->nonce, key + (keylen - CTR_RFC3686_NONCE_SIZE),
+ CTR_RFC3686_NONCE_SIZE);
+
+ keylen -= CTR_RFC3686_NONCE_SIZE;
+
+ crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
+ crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) &
+ CRYPTO_TFM_REQ_MASK);
+ return crypto_skcipher_setkey(child, key, keylen);
+}
+
+static int crypto_rfc3686_crypt(struct skcipher_request *req)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct crypto_rfc3686_ctx *ctx = crypto_skcipher_ctx(tfm);
+ struct crypto_skcipher *child = ctx->child;
+ unsigned long align = crypto_skcipher_alignmask(tfm);
+ struct crypto_rfc3686_req_ctx *rctx =
+ (void *)PTR_ALIGN((u8 *)skcipher_request_ctx(req), align + 1);
+ struct skcipher_request *subreq = &rctx->subreq;
+ u8 *iv = rctx->iv;
+
+ /* set up counter block */
+ memcpy(iv, ctx->nonce, CTR_RFC3686_NONCE_SIZE);
+ memcpy(iv + CTR_RFC3686_NONCE_SIZE, req->iv, CTR_RFC3686_IV_SIZE);
+
+ /* initialize counter portion of counter block */
+ *(__be32 *)(iv + CTR_RFC3686_NONCE_SIZE + CTR_RFC3686_IV_SIZE) =
+ cpu_to_be32(1);
+
+ skcipher_request_set_tfm(subreq, child);
+ skcipher_request_set_callback(subreq, req->base.flags,
+ req->base.complete, req->base.data);
+ skcipher_request_set_crypt(subreq, req->src, req->dst,
+ req->cryptlen, iv);
+
+ return crypto_skcipher_encrypt(subreq);
+}
+
+static int crypto_rfc3686_init_tfm(struct crypto_skcipher *tfm)
+{
+ struct skcipher_instance *inst = skcipher_alg_instance(tfm);
+ struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst);
+ struct crypto_rfc3686_ctx *ctx = crypto_skcipher_ctx(tfm);
+ struct crypto_skcipher *cipher;
+ unsigned long align;
+ unsigned int reqsize;
+
+ cipher = crypto_spawn_skcipher(spawn);
+ if (IS_ERR(cipher))
+ return PTR_ERR(cipher);
+
+ ctx->child = cipher;
+
+ align = crypto_skcipher_alignmask(tfm);
+ align &= ~(crypto_tfm_ctx_alignment() - 1);
+ reqsize = align + sizeof(struct crypto_rfc3686_req_ctx) +
+ crypto_skcipher_reqsize(cipher);
+ crypto_skcipher_set_reqsize(tfm, reqsize);
+
+ return 0;
+}
+
+static void crypto_rfc3686_exit_tfm(struct crypto_skcipher *tfm)
+{
+ struct crypto_rfc3686_ctx *ctx = crypto_skcipher_ctx(tfm);
+
+ crypto_free_skcipher(ctx->child);
+}
+
+static void crypto_rfc3686_free(struct skcipher_instance *inst)
+{
+ struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst);
+
+ crypto_drop_skcipher(spawn);
+ kfree(inst);
+}
+
+static int crypto_rfc3686_create(struct crypto_template *tmpl,
+ struct rtattr **tb)
+{
+ struct skcipher_instance *inst;
+ struct crypto_skcipher_spawn *spawn;
+ struct skcipher_alg_common *alg;
+ u32 mask;
+ int err;
+
+ err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, &mask);
+ if (err)
+ return err;
+
+ inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
+ if (!inst)
+ return -ENOMEM;
+
+ spawn = skcipher_instance_ctx(inst);
+
+ err = crypto_grab_skcipher(spawn, skcipher_crypto_instance(inst),
+ crypto_attr_alg_name(tb[1]), 0, mask);
+ if (err)
+ goto err_free_inst;
+
+ alg = crypto_spawn_skcipher_alg_common(spawn);
+
+ /* We only support 16-byte blocks. */
+ err = -EINVAL;
+ if (alg->ivsize != CTR_RFC3686_BLOCK_SIZE)
+ goto err_free_inst;
+
+ /* Not a stream cipher? */
+ if (alg->base.cra_blocksize != 1)
+ goto err_free_inst;
+
+ err = -ENAMETOOLONG;
+ if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+ "rfc3686(%s)", alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+ if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+ "rfc3686(%s)", alg->base.cra_driver_name) >=
+ CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ inst->alg.base.cra_priority = alg->base.cra_priority;
+ inst->alg.base.cra_blocksize = 1;
+ inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
+
+ inst->alg.ivsize = CTR_RFC3686_IV_SIZE;
+ inst->alg.chunksize = alg->chunksize;
+ inst->alg.min_keysize = alg->min_keysize + CTR_RFC3686_NONCE_SIZE;
+ inst->alg.max_keysize = alg->max_keysize + CTR_RFC3686_NONCE_SIZE;
+
+ inst->alg.setkey = crypto_rfc3686_setkey;
+ inst->alg.encrypt = crypto_rfc3686_crypt;
+ inst->alg.decrypt = crypto_rfc3686_crypt;
+
+ inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc3686_ctx);
+
+ inst->alg.init = crypto_rfc3686_init_tfm;
+ inst->alg.exit = crypto_rfc3686_exit_tfm;
+
+ inst->free = crypto_rfc3686_free;
+
+ err = skcipher_register_instance(tmpl, inst);
+ if (err) {
+err_free_inst:
+ crypto_rfc3686_free(inst);
+ }
+ return err;
+}
+
+static struct crypto_template crypto_ctr_tmpls[] = {
+ {
+ .name = "ctr",
+ .create = crypto_ctr_create,
+ .module = THIS_MODULE,
+ }, {
+ .name = "rfc3686",
+ .create = crypto_rfc3686_create,
+ .module = THIS_MODULE,
+ },
+};
+
+static int __init crypto_ctr_module_init(void)
+{
+ return crypto_register_templates(crypto_ctr_tmpls,
+ ARRAY_SIZE(crypto_ctr_tmpls));
+}
+
+static void __exit crypto_ctr_module_exit(void)
+{
+ crypto_unregister_templates(crypto_ctr_tmpls,
+ ARRAY_SIZE(crypto_ctr_tmpls));
+}
+
+module_init(crypto_ctr_module_init);
+module_exit(crypto_ctr_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("CTR block cipher mode of operation");
+MODULE_ALIAS_CRYPTO("rfc3686");
+MODULE_ALIAS_CRYPTO("ctr");
+MODULE_IMPORT_NS("CRYPTO_INTERNAL");