From 63db32e6531c1d47cf5bcd2082ed074fba4633ca Mon Sep 17 00:00:00 2001 From: Iuliana Prodan Date: Tue, 7 Apr 2020 01:47:27 +0300 Subject: [PATCH] crypto: caam - fix use-after-free KASAN issue for HASH algorithms Here's the KASAN report: BUG: KASAN: use-after-free in ahash_done+0xdc/0x3b8 Read of size 1 at addr ffff00002303f010 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.0-rc1-00162-gfcb90d5 #59 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 ahash_done+0xdc/0x3b8 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 ahash_edesc_alloc+0x58/0x1f8 ahash_final_no_ctx+0x94/0x6e8 ahash_final+0x24/0x30 crypto_ahash_op+0x58/0xb0 crypto_ahash_final+0x30/0x40 do_ahash_op+0x2c/0xa0 test_ahash_vec_cfg+0x894/0x9e0 test_hash_vec_cfg+0x6c/0x88 test_hash_vec+0xfc/0x1e0 __alg_test_hash+0x1ac/0x368 alg_test_hash+0xf8/0x1c8 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 ahash_done+0xd4/0x3b8 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 ffff00002303f000 which belongs to the cache dma-kmalloc-128 of size 128 The buggy address is located 16 bytes inside of 128-byte region [ffff00002303f000, ffff00002303f080) The buggy address belongs to the page: page:fffffe00006c0fc0 refcount:1 mapcount:0 mapping:ffff00093200c000 index:0x0 flags: 0xffff00000000200(slab) raw: 0ffff00000000200 dead000000000100 dead000000000122 ffff00093200c000 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff00002303ef00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff00002303ef80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff00002303f000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff00002303f080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff00002303f100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc Fixes: 21b014f038d3 ("crypto: caam - add crypto_engine support for HASH algorithms") Signed-off-by: Iuliana Prodan Signed-off-by: Herbert Xu --- drivers/crypto/caam/caamhash.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/crypto/caam/caamhash.c b/drivers/crypto/caam/caamhash.c index 943bc02..27ff4a3 100644 --- a/drivers/crypto/caam/caamhash.c +++ b/drivers/crypto/caam/caamhash.c @@ -583,10 +583,12 @@ static inline void ahash_done_cpy(struct device *jrdev, u32 *desc, u32 err, struct caam_hash_state *state = ahash_request_ctx(req); struct caam_hash_ctx *ctx = crypto_ahash_ctx(ahash); int ecode = 0; + bool has_bklog; dev_dbg(jrdev, "%s %d: err 0x%x\n", __func__, __LINE__, err); edesc = state->edesc; + has_bklog = edesc->bklog; if (err) ecode = caam_jr_strstatus(jrdev, err); @@ -603,7 +605,7 @@ static inline void ahash_done_cpy(struct device *jrdev, 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) req->base.complete(&req->base, ecode); else crypto_finalize_hash_request(jrp->engine, req, ecode); @@ -632,10 +634,12 @@ static inline void ahash_done_switch(struct device *jrdev, u32 *desc, u32 err, struct caam_hash_state *state = ahash_request_ctx(req); int digestsize = crypto_ahash_digestsize(ahash); int ecode = 0; + bool has_bklog; dev_dbg(jrdev, "%s %d: err 0x%x\n", __func__, __LINE__, err); edesc = state->edesc; + has_bklog = edesc->bklog; if (err) ecode = caam_jr_strstatus(jrdev, err); @@ -663,7 +667,7 @@ static inline void ahash_done_switch(struct device *jrdev, 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) req->base.complete(&req->base, ecode); else crypto_finalize_hash_request(jrp->engine, req, ecode); -- 2.7.4