From: Michael Neuling Date: Mon, 1 Jul 2013 04:19:50 +0000 (+1000) Subject: powerpc/hw_brk: Fix off by one error when validating DAWR region end X-Git-Tag: firefly_0821_release~6453^2~1514 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=3b743326ed2edd5e118950874f7bdaed5759f977;p=firefly-linux-kernel-4.4.55.git powerpc/hw_brk: Fix off by one error when validating DAWR region end commit e2a800beaca1f580945773e57d1a0e7cd37b1056 upstream. The Data Address Watchpoint Register (DAWR) on POWER8 can take a 512 byte range but this range must not cross a 512 byte boundary. Unfortunately we were off by one when calculating the end of the region, hence we were not allowing some breakpoint regions which were actually valid. This fixes this error. Signed-off-by: Michael Neuling Reported-by: Edjunior Barbosa Machado Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c index 1150ae7c22c3..f0b47d1a6b0e 100644 --- a/arch/powerpc/kernel/hw_breakpoint.c +++ b/arch/powerpc/kernel/hw_breakpoint.c @@ -176,7 +176,7 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp) length_max = 512 ; /* 64 doublewords */ /* DAWR region can't cross 512 boundary */ if ((bp->attr.bp_addr >> 10) != - ((bp->attr.bp_addr + bp->attr.bp_len) >> 10)) + ((bp->attr.bp_addr + bp->attr.bp_len - 1) >> 10)) return -EINVAL; } if (info->len >