Re: [PATCH v2 2/4] ima_violations.sh: Update validate() to support multiple violations

[Mimi Zohar <zohar@linux.ibm.com>]

On Tue, 2025-03-04 at 14:31 +0100, Petr Vorel wrote:
> Hi Mimi,
> 
> > Add support for the number of expected violations.  Include the
> > expected number of violations in the output.
> 
> Unfortunately this works only on fixed kernel (e.g. the one with v1 of your
> "ima: limit both open-writers and ToMToU violations" kernel patchset [1]
> (I haven't built v2 [2], but it's really just
> s/IMA_LIMIT_VIOLATIONS/IMA_EMITTED_OPENWRITERS/ => it will work)
> 
> Testing on any other kernel it fails on first testing after reboot:

Hi Petr,

I only tested by specifying the "ima_policy=tcb" on the boot command line.  This
failure happens when loading the test specific policy rules.  If setup() is
called before loading the test specific policy rules, forcing the $LOG file
violation at setup() would be too early.

Mimi

> 
> # LTP_IMA_LOAD_POLICY=1 LTPROOT="/opt/ltp" PATH="/opt/ltp/testcases/bin:$PATH" ima_violations.sh # openSUSE Tumbleweed 6.13, without your patch
> tmpfs is skipped
> ima_violations 1 TINFO: Running: ima_violations.sh
> ima_violations 1 TINFO: Tested kernel: Linux tss 6.13.1-1-default #1 SMP PREEMPT_DYNAMIC Mon Feb  3 05:33:25 UTC 2025 (1918d13) x86_64 x86_64 x86_64 GNU/Linux
> ima_violations 1 TINFO: Using /tmp/LTP_ima_violations.bbGjQQLJIx as tmpdir (tmpfs filesystem)
> tst_device.c:96: TINFO: Found free device 0 '/dev/loop0'
> ima_violations 1 TINFO: Formatting ext3 with opts='/dev/loop0'
> ima_violations 1 TINFO: Mounting device: mount -t ext3 /dev/loop0 /tmp/LTP_ima_violations.bbGjQQLJIx/mntpoint
> ima_violations 1 TINFO: timeout per run is 0h 5m 0s
> ima_violations 1 TINFO: IMA kernel config:
> ima_violations 1 TINFO: CONFIG_IMA=y
> ima_violations 1 TINFO: CONFIG_IMA_MEASURE_PCR_IDX=10
> ima_violations 1 TINFO: CONFIG_IMA_LSM_RULES=y
> ima_violations 1 TINFO: CONFIG_IMA_NG_TEMPLATE=y
> ima_violations 1 TINFO: CONFIG_IMA_DEFAULT_TEMPLATE="ima-ng"
> ima_violations 1 TINFO: CONFIG_IMA_DEFAULT_HASH_SHA256=y
> ima_violations 1 TINFO: CONFIG_IMA_DEFAULT_HASH="sha256"
> ima_violations 1 TINFO: CONFIG_IMA_READ_POLICY=y
> ima_violations 1 TINFO: CONFIG_IMA_APPRAISE=y
> ima_violations 1 TINFO: CONFIG_IMA_ARCH_POLICY=y
> ima_violations 1 TINFO: CONFIG_IMA_APPRAISE_BOOTPARAM=y
> ima_violations 1 TINFO: CONFIG_IMA_APPRAISE_MODSIG=y
> ima_violations 1 TINFO: CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS=y
> ima_violations 1 TINFO: CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS=y
> ima_violations 1 TINFO: CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT=y
> ima_violations 1 TINFO: CONFIG_IMA_DISABLE_HTABLE=y
> ima_violations 1 TINFO: /proc/cmdline: BOOT_IMAGE=/boot/vmlinuz-6.13.1-1-default root=UUID=1e7acd04-4289-49c9-ba76-a406b385cdc9 splash=silent video=1024x768 plymouth.ignore-serial-consoles console=ttyS0 console=tty kernel.softlockup_panic=1 mitigations=auto ignore_loglevel security=selinux selinux=1 enforcing=1 ima_policy=critical_data
> ima_violations 1 TINFO: $TMPDIR is on tmpfs => run on loop device
> ima_violations 1 TINFO: test requires IMA policy:
> measure func=FILE_CHECK mask=^MAY_READ euid=0
> measure func=FILE_CHECK mask=^MAY_READ uid=0
> ima_violations 1 TINFO: WARNING: missing required policy content: 'measure func=FILE_CHECK mask=^MAY_READ euid=0'
> ima_violations 1 TINFO: trying to load '/opt/ltp/testcases/data/ima_violations/violations.policy' policy:
> measure func=FILE_CHECK mask=^MAY_READ euid=0
> measure func=FILE_CHECK mask=^MAY_READ uid=0
> ima_violations 1 TINFO: example policy successfully loaded
> ima_violations 1 TINFO: using log /var/log/audit/audit.log
> ima_violations 1 TINFO: verify open writers violation
> ima_violations 1 TFAIL: open_writers too many violations added: 3 - 1
> ima_violations 2 TINFO: verify ToMToU violation
> ima_violations 2 TFAIL: ToMToU too many violations added: 6 - 4
> ima_violations 3 TINFO: verify open_writers using mmapped files
> tst_test.c:1900: TINFO: LTP version: 20250130
> tst_test.c:1904: TINFO: Tested kernel: 6.13.1-1-default #1 SMP PREEMPT_DYNAMIC Mon Feb  3 05:33:25 UTC 2025 (1918d13) x86_64
> tst_kconfig.c:88: TINFO: Parsing kernel config '/proc/config.gz'
> tst_kconfig.c:676: TINFO: CONFIG_FAULT_INJECTION kernel option detected which might slow the execution
> tst_test.c:1722: TINFO: Overall timeout per run is 0h 02m 00s
> ima_mmap.c:38: TINFO: sleep 3s
> ima_violations 3 TFAIL: open_writers too many violations added: 9 - 7
> ima_violations 4 TINFO: WARNING: policy loaded via LTP_IMA_LOAD_POLICY=1, reboot recommended
> ima_mmap.c:41: TPASS: test completed
> 
> It keeps failing repeatedly.
> I was able to reproduce the problem on SLE15-SP6 (6.4 based) and SLE15-SP4 (5.14 based).
> 
> I tried to test also some Debian VM. It fails when run after reboot:
> 
> # LTP_IMA_LOAD_POLICY=1 LTPROOT="/opt/ltp" PATH="/opt/ltp/testcases/bin:$PATH" ima_violations.sh # some Debian VM
> tmpfs is skipped
> ima_violations 1 TINFO: Running: ima_violations.sh
> ima_violations 1 TINFO: Tested kernel: Linux tt 6.9.9-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.9.9-1 (2024-07-13) x86_64 GNU/Linux
> ima_violations 1 TINFO: Using /tmp/LTP_ima_violations.RbX4HA7oZx as tmpdir (tmpfs filesystem)
> tst_device.c:96: TINFO: Found free device 0 '/dev/loop0'
> ima_violations 1 TINFO: Formatting ext3 with opts='/dev/loop0'
> ima_violations 1 TINFO: Mounting device: mount -t ext3 /dev/loop0 /tmp/LTP_ima_violations.RbX4HA7oZx/mntpoint
> ima_violations 1 TINFO: timeout per run is 0h 5m 0s
> ima_violations 1 TINFO: IMA kernel config:
> ima_violations 1 TINFO: CONFIG_IMA=y
> ima_violations 1 TINFO: CONFIG_IMA_MEASURE_PCR_IDX=10
> ima_violations 1 TINFO: CONFIG_IMA_LSM_RULES=y
> ima_violations 1 TINFO: CONFIG_IMA_SIG_TEMPLATE=y
> ima_violations 1 TINFO: CONFIG_IMA_DEFAULT_TEMPLATE="ima-sig"
> ima_violations 1 TINFO: CONFIG_IMA_DEFAULT_HASH_SHA256=y
> ima_violations 1 TINFO: CONFIG_IMA_DEFAULT_HASH="sha256"
> ima_violations 1 TINFO: CONFIG_IMA_APPRAISE=y
> ima_violations 1 TINFO: CONFIG_IMA_ARCH_POLICY=y
> ima_violations 1 TINFO: CONFIG_IMA_APPRAISE_BOOTPARAM=y
> ima_violations 1 TINFO: CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS=y
> ima_violations 1 TINFO: CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS=y
> ima_violations 1 TINFO: CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT=y
> ima_violations 1 TINFO: /proc/cmdline: BOOT_IMAGE=/boot/vmlinuz-6.9.9-amd64 root=UUID=e55db984-06ad-45d3-9707-dcaec157aebd ro quiet
> ima_violations 1 TINFO: $TMPDIR is on tmpfs => run on loop device
> ima_violations 1 TINFO: test requires IMA policy:
> measure func=FILE_CHECK mask=^MAY_READ euid=0
> measure func=FILE_CHECK mask=^MAY_READ uid=0
> ima_violations 1 TINFO: WARNING: policy is not readable, failure will be treated as TCONF
> ima_violations 1 TINFO: trying to load '/opt/ltp/testcases/data/ima_violations/violations.policy' policy:
> measure func=FILE_CHECK mask=^MAY_READ euid=0
> measure func=FILE_CHECK mask=^MAY_READ uid=0
> ima_violations 1 TINFO: example policy successfully loaded
> ima_violations 1 TINFO: using log /var/log/audit/audit.log
> ima_violations 1 TINFO: verify open writers violation
> ima_violations 1 TFAIL: open_writers too many violations added: 3 - 1
> ima_violations 2 TINFO: verify ToMToU violation
> ima_violations 2 TFAIL: ToMToU too many violations added: 6 - 4
> ima_violations 3 TINFO: verify open_writers using mmapped files
> tst_test.c:1890: TINFO: LTP version: 20240930-58-g15ce5997c
> tst_test.c:1894: TINFO: Tested kernel: 6.9.9-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.9.9-1 (2024-07-13) x86_64
> tst_test.c:1725: TINFO: Timeout per run is 0h 00m 30s
> ima_mmap.c:38: TINFO: sleep 3s
> ima_violations 3 TFAIL: open_writers too many violations added: 9 - 7
> ima_mmap.c:41: TPASS: test completed
> 
> Summary:
> passed   1
> failed   0
> broken   0
> skipped  0
> warnings 0
> ima_violations 4 TINFO: WARNING: policy loaded via LTP_IMA_LOAD_POLICY=1, reboot recommended
> 
> Summary:
> passed   0
> failed   3
> broken   0
> skipped  0
> warnings 0
> 
> But it TCONF when repeatedly run:
> 
> ima_violations 1 TCONF: open_writers too many violations added: 13 - 11
> ima_violations 2 TINFO: verify ToMToU violation
> ima_violations 2 TCONF: ToMToU too many violations added: 16 - 14
> ima_violations 3 TINFO: verify open_writers using mmapped files
> tst_test.c:1890: TINFO: LTP version: 20240930-58-g15ce5997c
> tst_test.c:1894: TINFO: Tested kernel: 6.9.9-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.9.9-1 (2024-07-13) x86_64
> tst_test.c:1725: TINFO: Timeout per run is 0h 00m 30s
> ima_mmap.c:38: TINFO: sleep 3s
> ima_violations 3 TCONF: open_writers too many violations added: 19 - 17
> 
> I guess this is not what you expected. I wonder what is wrong.
> 
> Kind regards,
> Petr
> 
> [1] https://lore.kernel.org/linux-integrity/20250219162131.416719-1-zohar@linux.ibm.com/
> [2] https://lore.kernel.org/linux-integrity/20250228205505.476845-1-zohar@linux.ibm.com/
>