From 8540571e01f973d321b0821f4f32ed6e9ae8263c Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 26 Aug 2016 16:45:13 +0200 Subject: powerpc/32: Fix again csum_partial_copy_generic() Commit 7aef4136566b0 ("powerpc32: rewrite csum_partial_copy_generic() based on copy_tofrom_user()") introduced a bug when destination address is odd and len is lower than cacheline size. In that case the resulting csum value doesn't have to be rotated one byte because the cache-aligned copy part is skipped so no alignment is performed. Fixes: 7aef4136566b0 ("powerpc32: rewrite csum_partial_copy_generic() based on copy_tofrom_user()") Cc: stable@vger.kernel.org # v4.6+ Reported-by: Alessio Igor Bogani Signed-off-by: Christophe Leroy Tested-by: Alessio Igor Bogani Signed-off-by: Michael Ellerman --- arch/powerpc/lib/checksum_32.S | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S index 0a57fe6d49cc..aa8214f30c92 100644 --- a/arch/powerpc/lib/checksum_32.S +++ b/arch/powerpc/lib/checksum_32.S @@ -127,18 +127,19 @@ _GLOBAL(csum_partial_copy_generic) stw r7,12(r1) stw r8,8(r1) - rlwinm r0,r4,3,0x8 - rlwnm r6,r6,r0,0,31 /* odd destination address: rotate one byte */ - cmplwi cr7,r0,0 /* is destination address even ? */ addic r12,r6,0 addi r6,r4,-4 neg r0,r4 addi r4,r3,-4 andi. r0,r0,CACHELINE_MASK /* # bytes to start of cache line */ + crset 4*cr7+eq beq 58f cmplw 0,r5,r0 /* is this more than total to do? */ blt 63f /* if not much to do */ + rlwinm r7,r6,3,0x8 + rlwnm r12,r12,r7,0,31 /* odd destination address: rotate one byte */ + cmplwi cr7,r7,0 /* is destination address even ? */ andi. r8,r0,3 /* get it word-aligned first */ mtctr r8 beq+ 61f -- cgit v1.2.3