From: Iuliana Prodan <iuliana.prodan@xxxxxxx> commit 55b3209acbb01cb02b1ee6b1afe80d83b1aab36d upstream. For skcipher algorithms, the input, output HW S/G tables look like this: [IV, src][dst, IV] Now, we can have 2 conditions here: - there is no IV; - src and dst are equal (in-place encryption) and scattered and the error is an "off-by-one" in the HW S/G table. This issue was seen with KASAN: BUG: KASAN: slab-out-of-bounds in skcipher_edesc_alloc+0x95c/0x1018 Read of size 4 at addr ffff000022a02958 by task cryptomgr_test/321 CPU: 2 PID: 321 Comm: cryptomgr_test Not tainted 5.6.0-rc1-00165-ge4ef8383-dirty #4 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_load4+0x90/0xb0 skcipher_edesc_alloc+0x95c/0x1018 skcipher_encrypt+0x84/0x150 crypto_skcipher_encrypt+0x50/0x68 test_skcipher_vec_cfg+0x4d4/0xc10 test_skcipher_vec+0x178/0x1d8 alg_test_skcipher+0xec/0x230 alg_test.part.44+0x114/0x4a0 alg_test+0x1c/0x60 cryptomgr_test+0x34/0x58 kthread+0x1b8/0x1c0 ret_from_fork+0x10/0x18 Allocated by task 321: save_stack+0x24/0xb0 __kasan_kmalloc.isra.10+0xc4/0xe0 kasan_kmalloc+0xc/0x18 __kmalloc+0x178/0x2b8 skcipher_edesc_alloc+0x21c/0x1018 skcipher_encrypt+0x84/0x150 crypto_skcipher_encrypt+0x50/0x68 test_skcipher_vec_cfg+0x4d4/0xc10 test_skcipher_vec+0x178/0x1d8 alg_test_skcipher+0xec/0x230 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: (stack is not available) The buggy address belongs to the object at ffff000022a02800 which belongs to the cache dma-kmalloc-512 of size 512 The buggy address is located 344 bytes inside of 512-byte region [ffff000022a02800, ffff000022a02a00) The buggy address belongs to the page: page:fffffe00006a8000 refcount:1 mapcount:0 mapping:ffff00093200c400 index:0x0 compound_mapcount: 0 flags: 0xffff00000010200(slab|head) raw: 0ffff00000010200 dead000000000100 dead000000000122 ffff00093200c400 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff000022a02800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff000022a02880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff000022a02900: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ^ ffff000022a02980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff000022a02a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc Fixes: 334d37c9e263 ("crypto: caam - update IV using HW support") Cc: <stable@xxxxxxxxxxxxxxx> # v5.3+ Signed-off-by: Iuliana Prodan <iuliana.prodan@xxxxxxx> Reviewed-by: Horia Geantă <horia.geanta@xxxxxxx> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/crypto/caam/caamalg.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/crypto/caam/caamalg.c +++ b/drivers/crypto/caam/caamalg.c @@ -1791,7 +1791,7 @@ static struct skcipher_edesc *skcipher_e if (ivsize || mapped_dst_nents > 1) sg_to_sec4_set_last(edesc->sec4_sg + dst_sg_idx + - mapped_dst_nents); + mapped_dst_nents - 1 + !!ivsize); if (sec4_sg_bytes) { edesc->sec4_sg_dma = dma_map_single(jrdev, edesc->sec4_sg,