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| author | Christophe Leroy <christophe.leroy@c-s.fr> | 2016-08-26 16:45:13 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-09-24 10:09:37 +0200 |
| commit | 63cbe6ea3b9dfaf4761cca70fda448b974ede463 (patch) | |
| tree | f82fe741d13626a70364fbdc15265f3fa370deda | |
| parent | 13c2ad632e69f96e0ab33439745b084d93319522 (diff) | |
| download | lwn-63cbe6ea3b9dfaf4761cca70fda448b974ede463.tar.gz lwn-63cbe6ea3b9dfaf4761cca70fda448b974ede463.zip | |
powerpc/32: Fix again csum_partial_copy_generic()
commit 8540571e01f973d321b0821f4f32ed6e9ae8263c upstream.
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 <alessio.bogani@elettra.eu>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Alessio Igor Bogani <alessio.bogani@elettra.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/powerpc/lib/checksum_32.S | 7 |
1 files 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 |