[net-next,v3,00/10] Some pktgen fixes/improvments

Message

Peter Seiderer Feb. 3, 2025, 5:01 p.m. UTC

While taking a look at '[PATCH net] pktgen: Avoid out-of-range in
get_imix_entries' ([1]) and '[PATCH net v2] pktgen: Avoid out-of-bounds access
in get_imix_entries' ([2], [3]) and doing some tests and code review I
detected that the /proc/net/pktgen/... parsing logic does not honour the
user given buffer bounds (resulting in out-of-bounds access).

This can be observed e.g. by the following simple test (sometimes the
old/'longer' previous value is re-read from the buffer):

	$ echo add_device lo@0 > /proc/net/pktgen/kpktgend_0

	$ echo "min_pkt_size 12345" > /proc/net/pktgen/lo\@0 && grep min_pkt_size /proc/net/pktgen/lo\@0
Params: count 1000  min_pkt_size: 12345  max_pkt_size: 0
Result: OK: min_pkt_size=12345

	$ echo -n "min_pkt_size 123" > /proc/net/pktgen/lo\@0 && grep min_pkt_size /proc/net/pktgen/lo\@0
Params: count 1000  min_pkt_size: 12345  max_pkt_size: 0
Result: OK: min_pkt_size=12345

	$ echo "min_pkt_size 123" > /proc/net/pktgen/lo\@0 && grep min_pkt_size /proc/net/pktgen/lo\@0
Params: count 1000  min_pkt_size: 123  max_pkt_size: 0
Result: OK: min_pkt_size=123

So fix the out-of-bounds access (and some minor findings) and add a simple
proc_net_pktgen selftest...

Regards,
Peter

Changes v2 -> v3:
 - new patch: 'net: pktgen: fix ctrl interface command parsing'
 - new patch: 'net: pktgen: fix mpls reset parsing'
 - tools/testing/selftests/net/proc_net_pktgen.c:
   - fix typo in change description ('v1 -> v1' and tyop)
   - rename some vars to better match usage
     add_loopback_0 -> thr_cmd_add_loopback_0
     rm_loopback_0 -> thr_cmd_rm_loopback_0
     wrong_ctrl_cmd -> wrong_thr_cmd
     legacy_ctrl_cmd -> legacy_thr_cmd
     ctrl_fd -> thr_fd
   - add ctrl interface tests

Changes v1 -> v2:
 - new patch: 'net: pktgen: fix hex32_arg parsing for short reads'
 - new patch: 'net: pktgen: fix 'rate 0' error handling (return -EINVAL)'
 - new patch: 'net: pktgen: fix 'ratep 0' error handling (return -EINVAL)'
 - net/core/pktgen.c: additional fix get_imix_entries() and get_labels()
 - tools/testing/selftests/net/proc_net_pktgen.c:
   - fix tyop not vs. nod (suggested by Jakub Kicinski)
   - fix misaligned line (suggested by Jakub Kicinski)
   - enable fomerly commented out CONFIG_XFRM dependent test (command spi),
     as CONFIG_XFRM is enabled via tools/testing/selftests/net/config
     CONFIG_XFRM_INTERFACE/CONFIG_XFRM_USER (suggestex by Jakub Kicinski)
   - add CONFIG_NET_PKTGEN=m to tools/testing/selftests/net/config
     (suggested by Jakub Kicinski)
   - add modprobe pktgen to FIXTURE_SETUP() (suggested by Jakub Kicinski)
   - fix some checkpatch warnings (Missing a blank line after declarations)
   - shrink line length by re-naming some variables (command -> cmd,
     device -> dev)
   - add 'rate 0' testcase
   - add 'ratep 0' testcase

[1] https://lore.kernel.org/netdev/[e-mail]/
[2] https://lore.kernel.org/netdev/[e-mail]/
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76201b5979768500bca362871db66d77cb4c225e

Peter Seiderer (10):
  net: pktgen: replace ENOTSUPP with EOPNOTSUPP
  net: pktgen: enable 'param=value' parsing
  net: pktgen: fix hex32_arg parsing for short reads
  net: pktgen: fix 'rate 0' error handling (return -EINVAL)
  net: pktgen: fix 'ratep 0' error handling (return -EINVAL)
  net: pktgen: fix ctrl interface command parsing
  net: pktgen: fix access outside of user given buffer in
    pktgen_thread_write()
  net: pktgen: fix access outside of user given buffer in
    pktgen_if_write()
  net: pktgen: fix mpls reset parsing
  selftest: net: add proc_net_pktgen

 net/core/pktgen.c                             | 257 ++++---
 tools/testing/selftests/net/Makefile          |   1 +
 tools/testing/selftests/net/config            |   1 +
 tools/testing/selftests/net/proc_net_pktgen.c | 650 ++++++++++++++++++
 4 files changed, 819 insertions(+), 90 deletions(-)
 create mode 100644 tools/testing/selftests/net/proc_net_pktgen.c