Commit 34c9a0ff authored Apr 16, 2015 by Herbert Xu Committed by Linus Torvalds Apr 15, 2015

crypto: fix broken crypto_register_instance() module handling



Commit 9c521a20 ("crypto: api - remove instance when test failed")
tried to grab a module reference count before the module was even set.

Worse, it then goes on to free the module reference count after it is
set so you quickly end up with a negative module reference count which
prevents people from using any instances belonging to that module.

This patch moves the module initialisation before the reference
count.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent eea3a002

crypto/algapi.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -525,12 +525,12 @@ int crypto_register_instance(struct crypto_template *tmpl,
		if (err)
		return err;

		if (unlikely(!crypto_mod_get(&inst->alg)))
		return -EAGAIN;

		inst->alg.cra_module = tmpl->module;
		inst->alg.cra_flags \|= CRYPTO_ALG_INSTANCE;

		if (unlikely(!crypto_mod_get(&inst->alg)))
		return -EAGAIN;

		down_write(&crypto_alg_sem);

		larval = __crypto_register_alg(&inst->alg);

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