tools/testing/selftests/ftrace/test.d/dynevent/add_remove_uprobe.tc

#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
# description: Generic dynamic event - add/remove/test uprobe events
# requires: uprobe_events

if ! which readelf > /dev/null 2>&1 ; then
  echo "No readelf found. skipped."
  exit_unresolved
fi

echo 0 > events/enable
echo > dynamic_events

REALBIN=`readlink -f /bin/sh`

# Get the entry point virtual address from ELF header
ENTRY=`readelf -hW ${REALBIN} | grep "Entry point" | awk '{print $NF}'`

# Convert virtual address to file offset: find the LOAD segment containing
# the entry point, then compute file_offset = e_entry - p_vaddr + p_offset.
# For PIE binaries this is a no-op (vaddr == file offset), but for non-PIE
# executables the virtual address is much larger than the file size and
# must be converted, otherwise uprobe_register() rejects it with -EINVAL.
ENTRY_DEC=$(printf '%d' "$ENTRY")
OFFSET=$ENTRY
while IFS= read -r line; do
    set -- $line
    [ "$1" = "LOAD" ] || continue
    VA_DEC=$(printf '%d' "$3")
    OFF_DEC=$(printf '%d' "$2")
    FSZ_DEC=$(printf '%d' "$5")
    if [ "$ENTRY_DEC" -ge "$VA_DEC" ] && [ "$ENTRY_DEC" -lt "$((VA_DEC + FSZ_DEC))" ]; then
        OFFSET=$(printf '0x%x' "$((ENTRY_DEC - VA_DEC + OFF_DEC))")
        break
    fi
done << EOF
$(readelf -lW ${REALBIN} | grep LOAD)
EOF

echo "p:myevent ${REALBIN}:${OFFSET}" >> uprobe_events

grep -q myevent uprobe_events
test -d events/uprobes/myevent

echo 1 > events/uprobes/myevent/enable
echo 'ls' | /bin/sh > /dev/null
echo 0 > events/uprobes/myevent/enable
grep -q myevent trace

echo "-:myevent" >> uprobe_events
! grep -q myevent uprobe_events

echo > uprobe_events

clear_trace