1

Revert "sh: Handle calling csum_partial with misaligned data"

This reverts commit cadc4e1a2b.

Commit cadc4e1a2b ("sh: Handle calling csum_partial with misaligned
data") causes bad checksum calculations on unaligned data. Reverting
it fixes the problem.

    # Subtest: checksum
    # module: checksum_kunit
    1..5
    # test_csum_fixed_random_inputs: ASSERTION FAILED at lib/checksum_kunit.c:500
    Expected ( u64)result == ( u64)expec, but
        ( u64)result == 53378 (0xd082)
        ( u64)expec == 33488 (0x82d0)
    # test_csum_fixed_random_inputs: pass:0 fail:1 skip:0 total:1
    not ok 1 test_csum_fixed_random_inputs
    # test_csum_all_carry_inputs: ASSERTION FAILED at lib/checksum_kunit.c:525
    Expected ( u64)result == ( u64)expec, but
        ( u64)result == 65281 (0xff01)
        ( u64)expec == 65280 (0xff00)
    # test_csum_all_carry_inputs: pass:0 fail:1 skip:0 total:1
    not ok 2 test_csum_all_carry_inputs
    # test_csum_no_carry_inputs: ASSERTION FAILED at lib/checksum_kunit.c:573
    Expected ( u64)result == ( u64)expec, but
        ( u64)result == 65535 (0xffff)
        ( u64)expec == 65534 (0xfffe)
    # test_csum_no_carry_inputs: pass:0 fail:1 skip:0 total:1
    not ok 3 test_csum_no_carry_inputs
    # test_ip_fast_csum: pass:1 fail:0 skip:0 total:1
    ok 4 test_ip_fast_csum
    # test_csum_ipv6_magic: pass:1 fail:0 skip:0 total:1
    ok 5 test_csum_ipv6_magic
 # checksum: pass:2 fail:3 skip:0 total:5
 # Totals: pass:2 fail:3 skip:0 total:5
not ok 22 checksum

Fixes: cadc4e1a2b ("sh: Handle calling csum_partial with misaligned data")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/20240324231804.841099-1-linux@roeck-us.net
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
This commit is contained in:
Guenter Roeck 2024-03-24 16:18:04 -07:00 committed by John Paul Adrian Glaubitz
parent 6516f1916b
commit b5319c9629

View File

@ -33,7 +33,8 @@
*/
/*
* asmlinkage __wsum csum_partial(const void *buf, int len, __wsum sum);
* unsigned int csum_partial(const unsigned char *buf, int len,
* unsigned int sum);
*/
.text
@ -45,31 +46,11 @@ ENTRY(csum_partial)
* Fortunately, it is easy to convert 2-byte alignment to 4-byte
* alignment for the unrolled loop.
*/
mov r5, r1
mov r4, r0
tst #3, r0 ! Check alignment.
bt/s 2f ! Jump if alignment is ok.
mov r4, r7 ! Keep a copy to check for alignment
tst #2, r0 ! Check alignment.
bt 2f ! Jump if alignment is ok.
!
tst #1, r0 ! Check alignment.
bt 21f ! Jump if alignment is boundary of 2bytes.
! buf is odd
tst r5, r5
add #-1, r5
bt 9f
mov.b @r4+, r0
extu.b r0, r0
addc r0, r6 ! t=0 from previous tst
mov r6, r0
shll8 r6
shlr16 r0
shlr8 r0
or r0, r6
mov r4, r0
tst #2, r0
bt 2f
21:
! buf is 2 byte aligned (len could be 0)
add #-2, r5 ! Alignment uses up two bytes.
cmp/pz r5 !
bt/s 1f ! Jump if we had at least two bytes.
@ -77,17 +58,16 @@ ENTRY(csum_partial)
bra 6f
add #2, r5 ! r5 was < 2. Deal with it.
1:
mov r5, r1 ! Save new len for later use.
mov.w @r4+, r0
extu.w r0, r0
addc r0, r6
bf 2f
add #1, r6
2:
! buf is 4 byte aligned (len could be 0)
mov r5, r1
mov #-5, r0
shld r0, r1
tst r1, r1
shld r0, r5
tst r5, r5
bt/s 4f ! if it's =0, go to 4f
clrt
.align 2
@ -109,31 +89,30 @@ ENTRY(csum_partial)
addc r0, r6
addc r2, r6
movt r0
dt r1
dt r5
bf/s 3b
cmp/eq #1, r0
! here, we know r1==0
addc r1, r6 ! add carry to r6
! here, we know r5==0
addc r5, r6 ! add carry to r6
4:
mov r5, r0
mov r1, r0
and #0x1c, r0
tst r0, r0
bt 6f
! 4 bytes or more remaining
mov r0, r1
shlr2 r1
bt/s 6f
mov r0, r5
shlr2 r5
mov #0, r2
5:
addc r2, r6
mov.l @r4+, r2
movt r0
dt r1
dt r5
bf/s 5b
cmp/eq #1, r0
addc r2, r6
addc r1, r6 ! r1==0 here, so it means add carry-bit
addc r5, r6 ! r5==0 here, so it means add carry-bit
6:
! 3 bytes or less remaining
mov r1, r5
mov #3, r0
and r0, r5
tst r5, r5
@ -159,16 +138,6 @@ ENTRY(csum_partial)
mov #0, r0
addc r0, r6
9:
! Check if the buffer was misaligned, if so realign sum
mov r7, r0
tst #1, r0
bt 10f
mov r6, r0
shll8 r6
shlr16 r0
shlr8 r0
or r0, r6
10:
rts
mov r6, r0