[PATCH v3 0/4] Improved seccomp logging

Tyler Hicks
2017-02-14T03:45:24Z

This patch set is the third revision of the following two previously
submitted patch sets:

v1: http://lkml.kernel.org/r/1483375990-14948-1-git-send-email-tyhicks@canonical.com
v1: http://lkml.kernel.org/r/1483377999-15019-2-git-send-email-tyhicks@canonical.com

v2: http://lkml.kernel.org/r/1486100262-32391-1-git-send-email-tyhicks@canonical.com

The patch set aims to address some known deficiencies in seccomp's current
logging capabilities:

1. Inability to log all filter actions.
2. Inability to selectively enable filtering; e.g. devs want noisy logging,
users want relative quiet.
3. Consistent behavior with audit enabled and disabled.
4. Inability to easily develop a filter due to the lack of a
permissive/complain mode.

Changes since v2 to address feedback from Kees:
- Patch 1
+ Log a warning when sysctl registration fails
+ Move comment describing SECCOMP_RET_*_NAME from PATCH 2
+ Document the actions_avail sysctl
- Patch 2
+ Inline seccomp_log()
+ Optimize logging for RET_ALLOW hot path
+ Use "{ }" for name buffer initialization
+ Make a copy of the ctl_table and only modify the copy
+ Rename max_action_to_log sysctl to log_max_action
+ Document the log_max_action sysctl
- Patch 3
+ Put some space between RET_LOG and RET_ALLOW for future actions
+ Separate the RET_ALLOW and RET_LOG cases in __seccomp_filter()
- Patch 4
+ Adjust the selftests for the updated RET_LOG value

Tyler

Tyler Hicks (4):
seccomp: Add sysctl to display available actions
seccomp: Add sysctl to configure actions that should be logged
seccomp: Create an action to log before allowing
seccomp: Add tests for SECCOMP_RET_LOG

Documentation/prctl/seccomp_filter.txt | 43 ++++++
Documentation/sysctl/kernel.txt | 1 +
include/linux/audit.h | 6 +-
include/uapi/linux/seccomp.h | 1 +
kernel/seccomp.c | 185 +++++++++++++++++++++++++-
tools/testing/selftests/seccomp/seccomp_bpf.c | 94 +++++++++++++
6 files changed, 322 insertions(+), 8 deletions(-)

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2.7.4