lkml.org 
[lkml]   [2020]   [Apr]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 4/4] crypto: caam - fix use-after-free KASAN issue for RSA algorithms
Date
Here's the KASAN report:
BUG: KASAN: use-after-free in rsa_pub_done+0x70/0xe8
Read of size 1 at addr ffff000023082014 by task swapper/0/0

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.0-rc1-00162-gfcb90d5 #60
Hardware name: LS1046A RDB Board (DT)
Call trace:
dump_backtrace+0x0/0x260
show_stack+0x14/0x20
dump_stack+0xe8/0x144
print_address_description.isra.11+0x64/0x348
__kasan_report+0x11c/0x230
kasan_report+0xc/0x18
__asan_load1+0x5c/0x68
rsa_pub_done+0x70/0xe8
caam_jr_dequeue+0x390/0x608
tasklet_action_common.isra.13+0x1ec/0x230
tasklet_action+0x24/0x30
efi_header_end+0x1a4/0x370
irq_exit+0x114/0x128
__handle_domain_irq+0x80/0xe0
gic_handle_irq+0x50/0xa0
el1_irq+0xb8/0x180
cpuidle_enter_state+0xa4/0x490
cpuidle_enter+0x48/0x70
call_cpuidle+0x44/0x70
do_idle+0x304/0x338
cpu_startup_entry+0x24/0x40
rest_init+0xf8/0x10c
arch_call_rest_init+0xc/0x14
start_kernel+0x774/0x7b4

Allocated by task 263:
save_stack+0x24/0xb0
__kasan_kmalloc.isra.10+0xc4/0xe0
kasan_kmalloc+0xc/0x18
__kmalloc+0x178/0x2b8
rsa_edesc_alloc+0x2cc/0xe10
caam_rsa_enc+0x9c/0x5f0
test_akcipher_one+0x78c/0x968
alg_test_akcipher+0x78/0xf8
alg_test.part.44+0x114/0x4a0
alg_test+0x1c/0x60
cryptomgr_test+0x34/0x58
kthread+0x1b8/0x1c0
ret_from_fork+0x10/0x18

Freed by task 0:
save_stack+0x24/0xb0
__kasan_slab_free+0x10c/0x188
kasan_slab_free+0x10/0x18
kfree+0x7c/0x298
rsa_pub_done+0x68/0xe8
caam_jr_dequeue+0x390/0x608
tasklet_action_common.isra.13+0x1ec/0x230
tasklet_action+0x24/0x30
efi_header_end+0x1a4/0x370

The buggy address belongs to the object at ffff000023082000
which belongs to the cache dma-kmalloc-256 of size 256
The buggy address is located 20 bytes inside of
256-byte region [ffff000023082000, ffff000023082100)
The buggy address belongs to the page:
page:fffffe00006c2080 refcount:1 mapcount:0 mapping:ffff00093200c200 index:0x0 compound_mapcount: 0
flags: 0xffff00000010200(slab|head)
raw: 0ffff00000010200 dead000000000100 dead000000000122 ffff00093200c200
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff000023081f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff000023081f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff000023082000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff000023082080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff000023082100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc

Fixes: bf53795025a2 ("crypto: caam - add crypto_engine support for RSA algorithms")
Cc: <stable@vger.kernel.org> # v5.6
Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
---
drivers/crypto/caam/caampkc.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/caam/caampkc.c b/drivers/crypto/caam/caampkc.c
index 4fcae37..2e44d68 100644
--- a/drivers/crypto/caam/caampkc.c
+++ b/drivers/crypto/caam/caampkc.c
@@ -121,11 +121,13 @@ static void rsa_pub_done(struct device *dev, u32 *desc, u32 err, void *context)
struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
struct rsa_edesc *edesc;
int ecode = 0;
+ bool has_bklog;

if (err)
ecode = caam_jr_strstatus(dev, err);

edesc = req_ctx->edesc;
+ has_bklog = edesc->bklog;

rsa_pub_unmap(dev, edesc, req);
rsa_io_unmap(dev, edesc, req);
@@ -135,7 +137,7 @@ static void rsa_pub_done(struct device *dev, u32 *desc, u32 err, void *context)
* If no backlog flag, the completion of the request is done
* by CAAM, not crypto engine.
*/
- if (!edesc->bklog)
+ if (!has_bklog)
akcipher_request_complete(req, ecode);
else
crypto_finalize_akcipher_request(jrp->engine, req, ecode);
@@ -152,11 +154,13 @@ static void rsa_priv_f_done(struct device *dev, u32 *desc, u32 err,
struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
struct rsa_edesc *edesc;
int ecode = 0;
+ bool has_bklog;

if (err)
ecode = caam_jr_strstatus(dev, err);

edesc = req_ctx->edesc;
+ has_bklog = edesc->bklog;

switch (key->priv_form) {
case FORM1:
@@ -176,7 +180,7 @@ static void rsa_priv_f_done(struct device *dev, u32 *desc, u32 err,
* If no backlog flag, the completion of the request is done
* by CAAM, not crypto engine.
*/
- if (!edesc->bklog)
+ if (!has_bklog)
akcipher_request_complete(req, ecode);
else
crypto_finalize_akcipher_request(jrp->engine, req, ecode);
--
2.1.0
\
 
 \ /
  Last update: 2020-04-07 00:48    [W:0.057 / U:0.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site