[PATCH 0/1] Fix Kasan test module run failed in RISCV architecture

[Nylon Chen]

When you run Kasan test module in RISCV architecture,"kmalloc_memmove_invalid_size()"
will be executed and then kernel will be hang in infinite loop as below:

[   26.228433] Memory state around the buggy address:
[   26.229824]  ffffffe066e11d00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
[   26.232098]  ffffffe066e11d80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
[   26.234461] >ffffffe066e11e00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
[   26.236650]                                            ^
[   26.238149]  ffffffe066e11e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   26.240400]  ffffffe066e11f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   26.242646]
==================================================================
[   26.245312]
==================================================================
[   26.247607] BUG: KASAN: slab-out-of-bounds in memmove+0x2e/0x8a
[   26.249160] Read of size 1 at addr ffffffe066e11e49 by task
insmod/106
[   26.250855]
[   26.251755] CPU: 0 PID: 106 Comm: insmod Tainted: G    B
5.8.7 #2
[   26.253454] Call Trace:
[   26.254509] [<ffffffe000203256>] walk_stackframe+0x0/0x128
[   26.256027] [<ffffffe000203530>] show_stack+0x2e/0x3a
[   26.257467] [<ffffffe0005ab9e0>] dump_stack+0x84/0xa0
[   26.258936] [<ffffffe000367120>]
print_address_description.isra.0+0x34/0x404
[   26.260686] [<ffffffe000367676>] kasan_report+0xda/0x132
[   26.262141] [<ffffffe000367a68>] __asan_load1+0x42/0x4a
[   26.263610] [<ffffffe0005c1c4c>] memmove+0x2e/0x8a
[   26.265241] [<ffffffdf81cdec26>]
kmalloc_memmove_invalid_size+0x94/0xaa [test_kasan]
[   26.267829] [<ffffffdf81cdfa2a>] kmalloc_tests_init+0x94/0x14a
[test_kasan]
[   26.269563] [<ffffffe0002000d8>] do_one_initcall+0x40/0x134
[   26.271106] [<ffffffe0002a2e5c>] do_init_module+0xc6/0x25c
[   26.272610] [<ffffffe0002a5692>] load_module+0x257a/0x2bf2
[   26.274096] [<ffffffe0002a5e70>] __do_sys_finit_module+0x7e/0x94
[   26.275676] [<ffffffe0002a5eaa>] sys_finit_module+0x10/0x18
[   26.277207] [<ffffffe000201690>] ret_from_syscall+0x0/0x2
[   26.278677]

.....

[  579.407314]  0x0
[  579.408267]  0x0
[  579.409222]  0x0
[  579.410198]  0x0
[  579.411206]  0x0
[  579.412151]  0x0
[  579.413122]  0x0
[  579.414080]  0x0
[  579.415026]  0x0
[  579.415964]  0x0
[  579.416912]  0x0
[  579.417871]  0x0
[  579.418834]  0x0
[  579.419781]  0x0
[  579.420738]  0x0
[  579.421841]  0x0
[  579.422805]  0x0
[  579.423764]  0x0
[  579.424696]  0x0
[  579.425638]  0x0
[  579.426599]  0x0
[  579.427538]  0x0
[  579.428467]  0x0

.....


if we define __HAVE_ARCH_MEMMOVE and port memmove to RISCV can fix it.

Signed-off-by: Nick Hu <nickhu at andestech.com>
Signed-off-by: Nick Hu <nick650823 at gmail.com>
Signed-off-by: Nylon Chen <nylon7 at andestech.com>

Nylon Chen (1):
  riscv: provide memmove implementation

 arch/riscv/include/asm/string.h |  8 ++---
 arch/riscv/kernel/riscv_ksyms.c |  2 ++
 arch/riscv/lib/Makefile         |  1 +
 arch/riscv/lib/memmove.S        | 64 +++++++++++++++++++++++++++++++++
 4 files changed, 71 insertions(+), 4 deletions(-)
 create mode 100644 arch/riscv/lib/memmove.S

-- 
2.17.1