Mimi Zohar 4f0496d8ff ima: based on policy warn about loading firmware (pre-allocated buffer) ... Some systems are memory constrained but they need to load very large firmwares. The firmware subsystem allows drivers to request this firmware be loaded from the filesystem, but this requires that the entire firmware be loaded into kernel memory first before it's provided to the driver. This can lead to a situation where we map the firmware twice, once to load the firmware into kernel memory and once to copy the firmware into the final resting place. To resolve this problem, commit a098ecd2fa ("firmware: support loading into a pre-allocated buffer") introduced request_firmware_into_buf() API that allows drivers to request firmware be loaded directly into a pre-allocated buffer. Do devices using pre-allocated memory run the risk of the firmware being accessible to the device prior to the completion of IMA's signature verification any more than when using two buffers? (Refer to mailing list discussion[1]). Only on systems with an IOMMU can the access be prevented. As long as the signature verification completes prior to the DMA map is performed, the device can not access the buffer. This implies that the same buffer can not be re-used. Can we ensure the buffer has not been DMA mapped before using the pre-allocated buffer? [1] https://lkml.org/lkml/2018/7/10/56 Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>		2018-07-16 12:31:57 -07:00
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Kconfig	ima: add build time policy	2018-07-16 12:31:57 -07:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
ima.h	ima: based on policy require signed kexec kernel images	2018-07-16 12:31:57 -07:00
ima_api.c	audit: use inline function to get audit context	2018-05-14 17:24:18 -04:00
ima_appraise.c	ima: Improvements in ima_appraise_measurement()	2018-03-25 07:26:30 -04:00
ima_crypto.c	ima: Fallback to the builtin hash algorithm	2018-03-25 07:26:32 -04:00
ima_fs.c	integrity: Add an integrity directory in securityfs	2018-05-17 08:03:07 -04:00
ima_init.c	tpm: use struct tpm_chip for tpm_chip_find_get()	2018-01-08 12:58:36 +02:00
ima_kexec.c	ima: Unify logging	2018-05-17 07:49:12 -04:00
ima_main.c	ima: based on policy warn about loading firmware (pre-allocated buffer)	2018-07-16 12:31:57 -07:00
ima_mok.c	KEYS: Use structure to capture key restriction function and data	2017-04-04 14:10:10 -07:00
ima_policy.c	ima: add build time policy	2018-07-16 12:31:57 -07:00
ima_queue.c	tpm: use struct tpm_chip for tpm_chip_find_get()	2018-01-08 12:58:36 +02:00
ima_template.c	ima: Fix line continuation format	2017-12-18 09:43:47 -05:00
ima_template_lib.c	ima: Unify logging	2018-05-17 07:49:12 -04:00
ima_template_lib.h	ima: introduce ima_parse_buf()	2017-06-21 14:37:12 -04:00