From: Zheng Zengkai <zhengzengkai@huawei.com>
To: <takedakn@nttdata.co.jp>, <penguin-kernel@I-love.SAKURA.ne.jp>,
<jmorris@namei.org>, <serge@hallyn.com>
Cc: <linux-security-module@vger.kernel.org>,
<linux-kernel@vger.kernel.org>, <weiyongjun1@huawei.com>,
<zhengzengkai@huawei.com>
Subject: [PATCH] tomoyo: Fix null pointer check
Date: Thu, 26 Nov 2020 22:38:15 +0800 [thread overview]
Message-ID: <20201126143815.67697-1-zhengzengkai@huawei.com> (raw)
Since tomoyo_memory_ok() will check for null pointer returned by
kzalloc() in tomoyo_assign_profile(), tomoyo_assign_namespace(),
tomoyo_get_name() and tomoyo_commit_ok(), then emit OOM warnings
if needed. And this is the expected behavior as informed by
Tetsuo Handa.
Let's add __GFP_NOWARN to kzalloc() in those related functions.
Besides, to achieve this goal, remove the null check for entry
right after kzalloc() in tomoyo_assign_namespace().
Fixes: 57c2590fb7fd ("TOMOYO: Update profile structure")
Fixes: bd03a3e4c9a9 ("TOMOYO: Add policy namespace support.")
Reported-by: Hulk Robot <hulkci@huawei.com>
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
---
security/tomoyo/common.c | 2 +-
security/tomoyo/domain.c | 4 +---
security/tomoyo/memory.c | 4 ++--
3 files changed, 4 insertions(+), 6 deletions(-)
diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c
index 4bee32bfe16d..bc54d3c8c70a 100644
--- a/security/tomoyo/common.c
+++ b/security/tomoyo/common.c
@@ -498,7 +498,7 @@ static struct tomoyo_profile *tomoyo_assign_profile
ptr = ns->profile_ptr[profile];
if (ptr)
return ptr;
- entry = kzalloc(sizeof(*entry), GFP_NOFS);
+ entry = kzalloc(sizeof(*entry), GFP_NOFS | __GFP_NOWARN);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
ptr = ns->profile_ptr[profile];
diff --git a/security/tomoyo/domain.c b/security/tomoyo/domain.c
index dc4ecc0b2038..c6e5cc5cc7cd 100644
--- a/security/tomoyo/domain.c
+++ b/security/tomoyo/domain.c
@@ -473,9 +473,7 @@ struct tomoyo_policy_namespace *tomoyo_assign_namespace(const char *domainname)
return ptr;
if (len >= TOMOYO_EXEC_TMPSIZE - 10 || !tomoyo_domain_def(domainname))
return NULL;
- entry = kzalloc(sizeof(*entry) + len + 1, GFP_NOFS);
- if (!entry)
- return NULL;
+ entry = kzalloc(sizeof(*entry) + len + 1, GFP_NOFS | __GFP_NOWARN);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
ptr = tomoyo_find_namespace(domainname, len);
diff --git a/security/tomoyo/memory.c b/security/tomoyo/memory.c
index 2e7fcfa923c9..1b570bde7a3b 100644
--- a/security/tomoyo/memory.c
+++ b/security/tomoyo/memory.c
@@ -73,7 +73,7 @@ bool tomoyo_memory_ok(void *ptr)
*/
void *tomoyo_commit_ok(void *data, const unsigned int size)
{
- void *ptr = kzalloc(size, GFP_NOFS);
+ void *ptr = kzalloc(size, GFP_NOFS | __GFP_NOWARN);
if (tomoyo_memory_ok(ptr)) {
memmove(ptr, data, size);
@@ -170,7 +170,7 @@ const struct tomoyo_path_info *tomoyo_get_name(const char *name)
atomic_inc(&ptr->head.users);
goto out;
}
- ptr = kzalloc(sizeof(*ptr) + len, GFP_NOFS);
+ ptr = kzalloc(sizeof(*ptr) + len, GFP_NOFS | __GFP_NOWARN);
if (tomoyo_memory_ok(ptr)) {
ptr->entry.name = ((char *) ptr) + sizeof(*ptr);
memmove((char *) ptr->entry.name, name, len);
--
2.20.1
reply other threads:[~2020-11-26 14:34 UTC|newest]
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