From: Ivan Delalande <[email protected]>

commit e08df079b23e2e982df15aa340bfbaf50f297504 upstream.

If the trapping instruction contains a ':', for a memory access through
segment registers for example, the sed substitution will insert the '*'
marker in the middle of the instruction instead of the line address:

        2b:   65 48 0f c7 0f          cmpxchg16b %gs:*(%rdi)          <-- 
trapping instruction

I started to think I had forgotten some quirk of the assembly syntax
before noticing that it was actually coming from the script.  Fix it to
add the address marker at the right place for these instructions:

        28:   49 8b 06                mov    (%r14),%rax
        2b:*  65 48 0f c7 0f          cmpxchg16b %gs:(%rdi)           <-- 
trapping instruction
        30:   0f 94 c0                sete   %al

Fixes: 18ff44b189e2 ("scripts/decodecode: make faulting insn ptr more robust")
Signed-off-by: Ivan Delalande <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Borislav Petkov <[email protected]>
Link: http://lkml.kernel.org/r/20200419223653.GA31248@visor
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 scripts/decodecode |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/scripts/decodecode
+++ b/scripts/decodecode
@@ -126,7 +126,7 @@ faultlinenum=$(( $(wc -l $T.oo  | cut -d
 faultline=`cat $T.dis | head -1 | cut -d":" -f2-`
 faultline=`echo "$faultline" | sed -e 's/\[/\\\[/g; s/\]/\\\]/g'`
 
-cat $T.oo | sed -e "${faultlinenum}s/^\(.*:\)\(.*\)/\1\*\2\t\t<-- trapping 
instruction/"
+cat $T.oo | sed -e "${faultlinenum}s/^\([^:]*:\)\(.*\)/\1\*\2\t\t<-- trapping 
instruction/"
 echo
 cat $T.aa
 cleanup


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