diff options
| author | Herbert Xu <herbert@gondor.apana.org.au> | 2006-12-10 10:45:28 +1100 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2007-02-07 09:20:58 +1100 |
| commit | fb469840b8c34b2f95b40a64b271f245cc1075b7 (patch) | |
| tree | 8013f8beb39c83b80be0e40195005b0482cea69b /crypto/digest.c | |
| parent | 62d0cfcb27cf755cebdc93ca95dabc83608007cd (diff) | |
[CRYPTO] all: Check for usage in hard IRQ context
Using blkcipher/hash crypto operations in hard IRQ context can lead
to random memory corruption due to the reuse of kmap_atomic slots.
Since crypto operations were never meant to be used in hard IRQ
contexts, this patch checks for such usage and returns an error
before kmap_atomic is performed.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/digest.c')
| -rw-r--r-- | crypto/digest.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/crypto/digest.c b/crypto/digest.c index 8f4593268ce..bc47af648cb 100644 --- a/crypto/digest.c +++ b/crypto/digest.c @@ -14,7 +14,9 @@ #include <linux/mm.h> #include <linux/errno.h> +#include <linux/hardirq.h> #include <linux/highmem.h> +#include <linux/kernel.h> #include <linux/module.h> #include <linux/scatterlist.h> @@ -29,8 +31,8 @@ static int init(struct hash_desc *desc) return 0; } -static int update(struct hash_desc *desc, - struct scatterlist *sg, unsigned int nbytes) +static int update2(struct hash_desc *desc, + struct scatterlist *sg, unsigned int nbytes) { struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm); unsigned int alignmask = crypto_tfm_alg_alignmask(tfm); @@ -81,6 +83,14 @@ static int update(struct hash_desc *desc, return 0; } +static int update(struct hash_desc *desc, + struct scatterlist *sg, unsigned int nbytes) +{ + if (WARN_ON_ONCE(in_irq())) + return -EDEADLK; + return update2(desc, sg, nbytes); +} + static int final(struct hash_desc *desc, u8 *out) { struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm); @@ -118,8 +128,11 @@ static int setkey(struct crypto_hash *hash, const u8 *key, unsigned int keylen) static int digest(struct hash_desc *desc, struct scatterlist *sg, unsigned int nbytes, u8 *out) { + if (WARN_ON_ONCE(in_irq())) + return -EDEADLK; + init(desc); - update(desc, sg, nbytes); + update2(desc, sg, nbytes); return final(desc, out); } |