The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From bb8e52e4906f148c2faf6656b5106cf7233e9301 Mon Sep 17 00:00:00 2001 From: Roberto Sassu roberto.sassu@huawei.com Date: Mon, 31 Jan 2022 18:11:39 +0100 Subject: [PATCH] ima: Allow template selection with ima_template[_fmt]= after ima_hash=
Commit c2426d2ad5027 ("ima: added support for new kernel cmdline parameter ima_template_fmt") introduced an additional check on the ima_template variable to avoid multiple template selection.
Unfortunately, ima_template could be also set by the setup function of the ima_hash= parameter, when it calls ima_template_desc_current(). This causes attempts to choose a new template with ima_template= or with ima_template_fmt=, after ima_hash=, to be ignored.
Achieve the goal of the commit mentioned with the new static variable template_setup_done, so that template selection requests after ima_hash= are not ignored.
Finally, call ima_init_template_list(), if not already done, to initialize the list of templates before lookup_template_desc() is called.
Reported-by: Guo Zihua guozihua@huawei.com Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Cc: stable@vger.kernel.org Fixes: c2426d2ad5027 ("ima: added support for new kernel cmdline parameter ima_template_fmt") Signed-off-by: Mimi Zohar zohar@linux.ibm.com
diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c index 694560396be0..db1ad6d7a57f 100644 --- a/security/integrity/ima/ima_template.c +++ b/security/integrity/ima/ima_template.c @@ -29,6 +29,7 @@ static struct ima_template_desc builtin_templates[] = {
static LIST_HEAD(defined_templates); static DEFINE_SPINLOCK(template_list); +static int template_setup_done;
static const struct ima_template_field supported_fields[] = { {.field_id = "d", .field_init = ima_eventdigest_init, @@ -101,10 +102,11 @@ static int __init ima_template_setup(char *str) struct ima_template_desc *template_desc; int template_len = strlen(str);
- if (ima_template) + if (template_setup_done) return 1;
- ima_init_template_list(); + if (!ima_template) + ima_init_template_list();
/* * Verify that a template with the supplied name exists. @@ -128,6 +130,7 @@ static int __init ima_template_setup(char *str) }
ima_template = template_desc; + template_setup_done = 1; return 1; } __setup("ima_template=", ima_template_setup); @@ -136,7 +139,7 @@ static int __init ima_template_fmt_setup(char *str) { int num_templates = ARRAY_SIZE(builtin_templates);
- if (ima_template) + if (template_setup_done) return 1;
if (template_desc_init_fields(str, NULL, NULL) < 0) { @@ -147,6 +150,7 @@ static int __init ima_template_fmt_setup(char *str)
builtin_templates[num_templates - 1].fmt = str; ima_template = builtin_templates + num_templates - 1; + template_setup_done = 1;
return 1; }