blob: 22b6c8910b182fd987402189add117ebc967b5e9 [file] [log] [blame]
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
#
# Test for mishandling of splice() on pseudofilesystems, which should catch
# bugs like 11990a5bd7e5 ("module: Correctly truncate sysfs sections output")
#
# Since splice fallback was removed as part of the set_fs() rework, many of these
# tests expect to fail now. See https://lore.kernel.org/lkml/202009181443.C2179FB@keescook/
set -e
DIR=$(dirname "$0")
ret=0
expect_success()
{
title="$1"
shift
echo "" >&2
echo "$title ..." >&2
set +e
"$@"
rc=$?
set -e
case "$rc" in
0)
echo "ok: $title succeeded" >&2
;;
1)
echo "FAIL: $title should work" >&2
ret=$(( ret + 1 ))
;;
*)
echo "FAIL: something else went wrong" >&2
ret=$(( ret + 1 ))
;;
esac
}
expect_failure()
{
title="$1"
shift
echo "" >&2
echo "$title ..." >&2
set +e
"$@"
rc=$?
set -e
case "$rc" in
0)
echo "FAIL: $title unexpectedly worked" >&2
ret=$(( ret + 1 ))
;;
1)
echo "ok: $title correctly failed" >&2
;;
*)
echo "FAIL: something else went wrong" >&2
ret=$(( ret + 1 ))
;;
esac
}
do_splice()
{
filename="$1"
bytes="$2"
expected="$3"
report="$4"
out=$("$DIR"/splice_read "$filename" "$bytes" | cat)
if [ "$out" = "$expected" ] ; then
echo " matched $report" >&2
return 0
else
echo " no match: '$out' vs $report" >&2
return 1
fi
}
test_splice()
{
filename="$1"
echo " checking $filename ..." >&2
full=$(cat "$filename")
rc=$?
if [ $rc -ne 0 ] ; then
return 2
fi
two=$(echo "$full" | grep -m1 . | cut -c-2)
# Make sure full splice has the same contents as a standard read.
echo " splicing 4096 bytes ..." >&2
if ! do_splice "$filename" 4096 "$full" "full read" ; then
return 1
fi
# Make sure a partial splice see the first two characters.
echo " splicing 2 bytes ..." >&2
if ! do_splice "$filename" 2 "$two" "'$two'" ; then
return 1
fi
return 0
}
### /proc/$pid/ has no splice interface; these should all fail.
expect_failure "proc_single_open(), seq_read() splice" test_splice /proc/$$/limits
expect_failure "special open(), seq_read() splice" test_splice /proc/$$/comm
### /proc/sys/ has a splice interface; these should all succeed.
expect_success "proc_handler: proc_dointvec_minmax() splice" test_splice /proc/sys/fs/nr_open
expect_success "proc_handler: proc_dostring() splice" test_splice /proc/sys/kernel/modprobe
expect_success "proc_handler: special read splice" test_splice /proc/sys/kernel/version
### /sys/ has no splice interface; these should all fail.
if ! [ -d /sys/module/test_module/sections ] ; then
expect_success "test_module kernel module load" modprobe test_module
fi
expect_failure "kernfs attr splice" test_splice /sys/module/test_module/coresize
expect_failure "kernfs binattr splice" test_splice /sys/module/test_module/sections/.init.text
exit $ret