[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>
diff --git a/crypto/blkcipher.c b/crypto/blkcipher.c
index 6e93004f..cbb4c4e 100644
--- a/crypto/blkcipher.c
+++ b/crypto/blkcipher.c
@@ -16,6 +16,7 @@
#include <linux/crypto.h>
#include <linux/errno.h>
+#include <linux/hardirq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
@@ -313,6 +314,9 @@
struct crypto_blkcipher *tfm = desc->tfm;
unsigned int alignmask = crypto_blkcipher_alignmask(tfm);
+ if (WARN_ON_ONCE(in_irq()))
+ return -EDEADLK;
+
walk->nbytes = walk->total;
if (unlikely(!walk->total))
return 0;
diff --git a/crypto/digest.c b/crypto/digest.c
index 8f45932..bc47af6 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 @@
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 @@
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 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);
}
diff --git a/crypto/xcbc.c b/crypto/xcbc.c
index 9347eb6..317e9f08 100644
--- a/crypto/xcbc.c
+++ b/crypto/xcbc.c
@@ -21,6 +21,7 @@
#include <linux/crypto.h>
#include <linux/err.h>
+#include <linux/hardirq.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/rtnetlink.h>
@@ -108,9 +109,9 @@
return 0;
}
-static int crypto_xcbc_digest_update(struct hash_desc *pdesc,
- struct scatterlist *sg,
- unsigned int nbytes)
+static int crypto_xcbc_digest_update2(struct hash_desc *pdesc,
+ struct scatterlist *sg,
+ unsigned int nbytes)
{
struct crypto_hash *parent = pdesc->tfm;
struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent);
@@ -183,6 +184,15 @@
return 0;
}
+static int crypto_xcbc_digest_update(struct hash_desc *pdesc,
+ struct scatterlist *sg,
+ unsigned int nbytes)
+{
+ if (WARN_ON_ONCE(in_irq()))
+ return -EDEADLK;
+ return crypto_xcbc_digest_update2(pdesc, sg, nbytes);
+}
+
static int crypto_xcbc_digest_final(struct hash_desc *pdesc, u8 *out)
{
struct crypto_hash *parent = pdesc->tfm;
@@ -234,8 +244,11 @@
static int crypto_xcbc_digest(struct hash_desc *pdesc,
struct scatterlist *sg, unsigned int nbytes, u8 *out)
{
+ if (WARN_ON_ONCE(in_irq()))
+ return -EDEADLK;
+
crypto_xcbc_digest_init(pdesc);
- crypto_xcbc_digest_update(pdesc, sg, nbytes);
+ crypto_xcbc_digest_update2(pdesc, sg, nbytes);
return crypto_xcbc_digest_final(pdesc, out);
}