[PATCH] tomoyo: Fix null pointer check
From: Zheng Zengkai <hidden>
Date: 2020-11-26 14:34:25
Also in:
lkml
Subsystem:
security subsystem, the rest, tomoyo security module · Maintainers:
Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds, Kentaro Takeda, Tetsuo Handa
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 <redacted>
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Zheng Zengkai <redacted>
---
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