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author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-07-09 23:09:30 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-07-09 23:09:30 +0300 |
commit | ce69fb3b392fbfd6c255aeb0ee371652478c716f (patch) | |
tree | d043b0839d524c54f6b74b134ee6fb6f5dbaf3b2 /tools | |
parent | 0bddd227f3dc55975e2b8dfa7fc6f959b062a2c7 (diff) | |
parent | 2c79583927bb8154ecaa45a67dde97661d895ecd (diff) | |
download | linux-ce69fb3b392fbfd6c255aeb0ee371652478c716f.tar.xz |
Merge tag 'kallsyms_show_value-v5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull kallsyms fix from Kees Cook:
"Refactor kallsyms_show_value() users for correct cred.
I'm not delighted by the timing of getting these changes to you, but
it does fix a handful of kernel address exposures, and no one has
screamed yet at the patches.
Several users of kallsyms_show_value() were performing checks not
during "open". Refactor everything needed to gain proper checks
against file->f_cred for modules, kprobes, and bpf"
* tag 'kallsyms_show_value-v5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
selftests: kmod: Add module address visibility test
bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok()
kprobes: Do not expose probe addresses to non-CAP_SYSLOG
module: Do not expose section addresses to non-CAP_SYSLOG
module: Refactor section attr into bin attribute
kallsyms: Refactor kallsyms_show_value() to take cred
Diffstat (limited to 'tools')
-rwxr-xr-x | tools/testing/selftests/kmod/kmod.sh | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/tools/testing/selftests/kmod/kmod.sh b/tools/testing/selftests/kmod/kmod.sh index 3702dbcc90a7..c82aa77958e5 100755 --- a/tools/testing/selftests/kmod/kmod.sh +++ b/tools/testing/selftests/kmod/kmod.sh @@ -63,6 +63,8 @@ ALL_TESTS="$ALL_TESTS 0008:150:1" ALL_TESTS="$ALL_TESTS 0009:150:1" ALL_TESTS="$ALL_TESTS 0010:1:1" ALL_TESTS="$ALL_TESTS 0011:1:1" +ALL_TESTS="$ALL_TESTS 0012:1:1" +ALL_TESTS="$ALL_TESTS 0013:1:1" # Kselftest framework requirement - SKIP code is 4. ksft_skip=4 @@ -470,6 +472,38 @@ kmod_test_0011() echo "$MODPROBE" > /proc/sys/kernel/modprobe } +kmod_check_visibility() +{ + local name="$1" + local cmd="$2" + + modprobe $DEFAULT_KMOD_DRIVER + + local priv=$(eval $cmd) + local unpriv=$(capsh --drop=CAP_SYSLOG -- -c "$cmd") + + if [ "$priv" = "$unpriv" ] || \ + [ "${priv:0:3}" = "0x0" ] || \ + [ "${unpriv:0:3}" != "0x0" ] ; then + echo "${FUNCNAME[0]}: FAIL, $name visible to unpriv: '$priv' vs '$unpriv'" >&2 + exit 1 + else + echo "${FUNCNAME[0]}: OK!" + fi +} + +kmod_test_0012() +{ + kmod_check_visibility /proc/modules \ + "grep '^${DEFAULT_KMOD_DRIVER}\b' /proc/modules | awk '{print \$NF}'" +} + +kmod_test_0013() +{ + kmod_check_visibility '/sys/module/*/sections/*' \ + "cat /sys/module/${DEFAULT_KMOD_DRIVER}/sections/.*text | head -n1" +} + list_tests() { echo "Test ID list:" @@ -489,6 +523,8 @@ list_tests() echo "0009 x $(get_test_count 0009) - multithreaded - push kmod_concurrent over max_modprobes for get_fs_type()" echo "0010 x $(get_test_count 0010) - test nonexistent modprobe path" echo "0011 x $(get_test_count 0011) - test completely disabling module autoloading" + echo "0012 x $(get_test_count 0012) - test /proc/modules address visibility under CAP_SYSLOG" + echo "0013 x $(get_test_count 0013) - test /sys/module/*/sections/* visibility under CAP_SYSLOG" } usage() |