Home | History | Annotate | Download | only in kprobe 
      1 #!/bin/sh
      2 # SPDX-License-Identifier: GPL-2.0
      3 # description: Kprobe event argument syntax
      4 
      5 [ -f kprobe_events ] || exit_unsupported # this is configurable
      6 
      7 grep "x8/16/32/64" README > /dev/null || exit_unsupported # version issue
      8 
      9 PROBEFUNC="vfs_read"
     10 GOODREG=
     11 BADREG=
     12 GOODSYM="_sdata"
     13 if ! grep -qw ${GOODSYM} /proc/kallsyms ; then
     14   GOODSYM=$PROBEFUNC
     15 fi
     16 BADSYM="deaqswdefr"
     17 SYMADDR=0x`grep -w ${GOODSYM} /proc/kallsyms | cut -f 1 -d " "`
     18 GOODTYPE="x16"
     19 BADTYPE="y16"
     20 
     21 case `uname -m` in
     22 x86_64|i[3456]86)
     23   GOODREG=%ax
     24   BADREG=%ex
     25 ;;
     26 aarch64)
     27   GOODREG=%x0
     28   BADREG=%ax
     29 ;;
     30 arm*)
     31   GOODREG=%r0
     32   BADREG=%ax
     33 ;;
     34 ppc*)
     35   GOODREG=%r3
     36   BADREG=%msr
     37 ;;
     38 *)
     39   echo "Please implement other architecture here"
     40   exit_untested
     41 esac
     42 
     43 test_goodarg() # Good-args
     44 {
     45   while [ "$1" ]; do
     46     echo "p ${PROBEFUNC} $1" > kprobe_events
     47     shift 1
     48   done;
     49 }
     50 
     51 test_badarg() # Bad-args
     52 {
     53   while [ "$1" ]; do
     54     ! echo "p ${PROBEFUNC} $1" > kprobe_events
     55     shift 1
     56   done;
     57 }
     58 
     59 echo > kprobe_events
     60 
     61 : "Register access"
     62 test_goodarg ${GOODREG}
     63 test_badarg ${BADREG}
     64 
     65 : "Symbol access"
     66 test_goodarg "@${GOODSYM}" "@${SYMADDR}" "@${GOODSYM}+10" "@${GOODSYM}-10"
     67 test_badarg "@" "@${BADSYM}" "@${GOODSYM}*10" "@${GOODSYM}/10" \
     68 	    "@${GOODSYM}%10" "@${GOODSYM}&10" "@${GOODSYM}|10"
     69 
     70 : "Stack access"
     71 test_goodarg "\$stack" "\$stack0" "\$stack1"
     72 test_badarg "\$stackp" "\$stack0+10" "\$stack1-10"
     73 
     74 : "Retval access"
     75 echo "r ${PROBEFUNC} \$retval" > kprobe_events
     76 ! echo "p ${PROBEFUNC} \$retval" > kprobe_events
     77 
     78 # $comm was introduced in 4.8, older kernels reject it.
     79 if grep -A1 "fetcharg:" README | grep -q '\$comm' ; then
     80 : "Comm access"
     81 test_goodarg "\$comm"
     82 fi
     83 
     84 : "Indirect memory access"
     85 test_goodarg "+0(${GOODREG})" "-0(${GOODREG})" "+10(\$stack)" \
     86 	"+0(\$stack1)" "+10(@${GOODSYM}-10)" "+0(+10(+20(\$stack)))"
     87 test_badarg "+(${GOODREG})" "(${GOODREG}+10)" "-(${GOODREG})" "(${GOODREG})" \
     88 	"+10(\$comm)" "+0(${GOODREG})+10"
     89 
     90 : "Name assignment"
     91 test_goodarg "varname=${GOODREG}"
     92 test_badarg "varname=varname2=${GOODREG}"
     93 
     94 : "Type syntax"
     95 test_goodarg "${GOODREG}:${GOODTYPE}"
     96 test_badarg "${GOODREG}::${GOODTYPE}" "${GOODREG}:${BADTYPE}" \
     97 	"${GOODTYPE}:${GOODREG}"
     98 
     99 : "Combination check"
    100 
    101 test_goodarg "\$comm:string" "+0(\$stack):string"
    102 test_badarg "\$comm:x64" "\$stack:string" "${GOODREG}:string"
    103