From: "Petr Tesařík" <petr@tesarici.cz>
To: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Cc: zohar@linux.ibm.com, roberto.sassu@huaweicloud.com,
roberto.sassu@huawei.com, eric.snowberg@oracle.com,
stefanb@linux.ibm.com, ebiederm@xmission.com, noodles@fb.com,
bauermann@kolabnow.com, linux-integrity@vger.kernel.org,
kexec@lists.infradead.org, code@tyhicks.com,
nramas@linux.microsoft.com, paul@paul-moore.com
Subject: Re: [PATCH v5 5/8] ima: kexec: move IMA log copy from kexec load to execute
Date: Thu, 9 May 2024 08:32:05 +0200 [thread overview]
Message-ID: <20240509083205.17d53ccb@meshulam.tesarici.cz> (raw)
In-Reply-To: <20240214153827.1087657-6-tusharsu@linux.microsoft.com>
On Wed, 14 Feb 2024 07:38:24 -0800
Tushar Sugandhi <tusharsu@linux.microsoft.com> wrote:
> ima_dump_measurement_list() is called during kexec 'load', which may
> result in loss of IMA measurements during kexec soft reboot. It needs
> to be called during kexec 'execute'.
>
> This patch includes the following changes:
> - Call kimage_file_post_load() from kexec_file_load() syscall only for
> kexec soft reboot scenarios and not for KEXEC_FILE_ON_CRASH. It will
> map the IMA segment, and register reboot notifier for the function
> ima_update_kexec_buffer() which would copy the IMA log at kexec soft
> reboot.
> - Make kexec_segment_size variable local static to the file, for it to be
> accessible both during kexec 'load' and 'execute'.
> - Move ima_dump_measurement_list() call from ima_add_kexec_buffer()
> to ima_update_kexec_buffer().
> - Remove ima_reset_kexec_file() call from ima_add_kexec_buffer(), now
> that the buffer is being copied at kexec 'execute', and resetting the
> file at kexec 'load' will corrupt the buffer.
>
> Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
> ---
> kernel/kexec_file.c | 3 ++
> security/integrity/ima/ima_kexec.c | 45 +++++++++++++++++++-----------
> 2 files changed, 32 insertions(+), 16 deletions(-)
>
> diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> index fe59cb7c179d..2d5df320c34f 100644
> --- a/kernel/kexec_file.c
> +++ b/kernel/kexec_file.c
> @@ -410,6 +410,9 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
>
> kimage_terminate(image);
>
> + if (!(flags & KEXEC_FILE_ON_CRASH))
> + kimage_file_post_load(image);
> +
> ret = machine_kexec_post_load(image);
> if (ret)
> goto out;
> diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c
> index 1d4d6c122d82..98fc9b9782a2 100644
> --- a/security/integrity/ima/ima_kexec.c
> +++ b/security/integrity/ima/ima_kexec.c
> @@ -19,6 +19,7 @@
> #ifdef CONFIG_IMA_KEXEC
> static struct seq_file ima_kexec_file;
> static void *ima_kexec_buffer;
> +static size_t kexec_segment_size;
> static bool ima_kexec_update_registered;
>
> static void ima_reset_kexec_file(struct seq_file *sf)
> @@ -129,7 +130,6 @@ void ima_add_kexec_buffer(struct kimage *image)
> /* use more understandable variable names than defined in kbuf */
> void *kexec_buffer = NULL;
> size_t kexec_buffer_size;
> - size_t kexec_segment_size;
> int ret;
>
> /*
> @@ -154,14 +154,6 @@ void ima_add_kexec_buffer(struct kimage *image)
> return;
> }
>
> - ret = ima_dump_measurement_list(&kexec_buffer_size, &kexec_buffer,
> - kexec_segment_size);
> - if (ret < 0) {
> - pr_err("%s: Failed to dump IMA measurements. Error:%d.\n",
> - __func__, ret);
> - return;
> - }
> -
After removing these lines...
> kbuf.buffer = kexec_buffer;
> kbuf.bufsz = kexec_buffer_size;
^^^^^^^^^^^^^^^^^
... kexec_buffer_size is uninitialized here.
Petr T
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kexec@lists.infradead.org
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next prev parent reply other threads:[~2024-05-09 6:32 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-02-14 15:38 [PATCH v5 0/8] ima: kexec: measure events between kexec load and execute Tushar Sugandhi
2024-02-14 15:38 ` [PATCH v5 1/8] ima: define and call ima_alloc_kexec_file_buf Tushar Sugandhi
2024-02-19 22:16 ` Stefan Berger
2024-02-21 0:12 ` Mimi Zohar
2024-02-14 15:38 ` [PATCH v5 2/8] kexec: define functions to map and unmap segments Tushar Sugandhi
2024-02-14 19:43 ` Stefan Berger
2024-02-15 6:13 ` Tushar Sugandhi
2024-02-21 20:22 ` Mimi Zohar
2024-02-14 15:38 ` [PATCH v5 3/8] ima: kexec: skip IMA segment validation after kexec soft reboot Tushar Sugandhi
2024-02-14 15:38 ` [PATCH v5 4/8] ima: kexec: define functions to copy IMA log at soft boot Tushar Sugandhi
2024-02-14 20:47 ` Stefan Berger
2024-02-15 6:55 ` Tushar Sugandhi
2024-02-21 21:52 ` Mimi Zohar
2024-02-21 22:39 ` Mimi Zohar
2024-03-01 11:12 ` Petr Tesařík
2024-02-14 15:38 ` [PATCH v5 5/8] ima: kexec: move IMA log copy from kexec load to execute Tushar Sugandhi
2024-02-14 20:58 ` Stefan Berger
2024-02-22 1:47 ` Mimi Zohar
2024-05-09 6:32 ` Petr Tesařík [this message]
2024-02-14 15:38 ` [PATCH v5 6/8] ima: suspend measurements during buffer copy at kexec execute Tushar Sugandhi
2024-02-22 14:14 ` Mimi Zohar
2024-02-22 16:38 ` Mimi Zohar
2024-02-29 13:21 ` Petr Tesařík
2024-02-14 15:38 ` [PATCH v5 7/8] ima: make the kexec extra memory configurable Tushar Sugandhi
2024-02-22 14:13 ` Mimi Zohar
2024-02-14 15:38 ` [PATCH v5 8/8] ima: measure kexec load and exec events as critical data Tushar Sugandhi
2024-02-14 21:00 ` Stefan Berger
2024-02-15 6:57 ` Tushar Sugandhi
2024-02-14 21:03 ` Stefan Berger
2024-02-15 6:58 ` Tushar Sugandhi
2024-02-21 0:15 ` [PATCH v5 0/8] ima: kexec: measure events between kexec load and execute Mimi Zohar
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