Re: [RFC PATCH 3/3] ima: additional ToMToU violation tests

[Petr Vorel <pvorel@suse.cz>]

Hi Mimi,

> Kernel patch "ima: limit the number of ToMToU integrity violations"
> prevents superfluous ToMToU violations.  Add corresponding LTP tests.

> Link: https://lore.kernel.org/linux-integrity/20250219162131.416719-3-zohar@linux.ibm.com/
> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

Unfortunately tests fail on both mainline kernel and kernel with your patches.

Any hint what could be wrong?

Mainline kernel (on kernel with your patches it looks the same):
ima_violations 1 TINFO: Running: ima_violations.sh
ima_violations 1 TINFO: Tested kernel: Linux ts 6.13.0-2.g0127a37-default #1 SMP PREEMPT_DYNAMIC Thu Jan 23 11:21:55 UTC 2025 (0127a37) x86_64 x86_64 x86_64 GNU/Linux
ima_violations 1 TINFO: Using /tmp/LTP_ima_violations.cKm34XVZk2 as tmpdir (tmpfs filesystem)
tst_device.c:99: 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.cKm34XVZk2/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-6.13.0-2.g0127a37-default root=UUID=e36b2366-1af2-4408-903c-1fca82c60f4c splash=silent video=1024x768 plymouth.ignore-serial-consoles console=ttyS0 console=tty kernel.softlockup_panic=1 resume=/dev/disk/by-uuid/c3b865f9-5d5b-410e-a6d1-9ebcf721584c mitigations=auto security=apparmor ignore_loglevel
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: SUT has required policy content
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
ima_violations 2 TINFO: verify ToMToU violation
ima_violations 2 TFAIL: ToMToU too many violations added
ima_violations 3 TINFO: verify open_writers using mmapped files
tst_test.c:1900: TINFO: LTP version: 20250130-22-gcd2215702f
tst_test.c:1904: TINFO: Tested kernel: 6.13.0-2.g0127a37-default #1 SMP PREEMPT_DYNAMIC Thu Jan 23 11:21:55 UTC 2025 (0127a37) 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
ima_mmap.c:41: TPASS: test completed

Summary:
passed   1
failed   0
broken   0
skipped  0
warnings 0
ima_violations 4 TINFO: verify limiting single open writer violation
ima_violations 4 TFAIL: open_writers too many violations added
ima_violations 5 TINFO: verify limiting multiple open writers violations
ima_violations 5 TFAIL: open_writers too many violations added
ima_violations 6 TINFO: verify new open writer causes additional violation
ima_violations 6 TFAIL: open_writers too many violations added
ima_violations 7 TINFO: verify limiting single open reader ToMToU violations
ima_violations 7 TFAIL: ToMToU too many violations added
ima_violations 8 TINFO: verify new open reader causes additional ToMToU violation
ima_violations 8 TFAIL: ToMToU too many violations added

Kind regards,
Petr