The patch titled
Subject: ipc/sem: do not use ipc_rcu_free()
has been added to the -mm tree. Its filename is
ipc-sem-do-not-use-ipc_rcu_free.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/ipc-sem-do-not-use-ipc_rcu_free.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/ipc-sem-do-not-use-ipc_rcu_free.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Kees Cook <keescook@xxxxxxxxxxxx>
Subject: ipc/sem: do not use ipc_rcu_free()
Avoid using ipc_rcu_free, since it just re-finds the original structure
pointer. For the pre-list-init failure path, there is no RCU needed,
since it was just allocated. It can be directly freed.
Link: http://lkml.kernel.org/r/20170525185107.12869-6-manfred@xxxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>
Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
ipc/sem.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff -puN ipc/sem.c~ipc-sem-do-not-use-ipc_rcu_free ipc/sem.c
--- a/ipc/sem.c~ipc-sem-do-not-use-ipc_rcu_free
+++ a/ipc/sem.c
@@ -258,13 +258,18 @@ static void merge_queues(struct sem_arra
}
}
+static void __sem_free(struct sem_array *sma)
+{
+ kvfree(sma);
+}
+
static void sem_rcu_free(struct rcu_head *head)
{
struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu);
struct sem_array *sma = container_of(p, struct sem_array, sem_perm);
security_sem_free(sma);
- ipc_rcu_free(head);
+ __sem_free(sma);
}
/*
@@ -482,7 +487,7 @@ static int newary(struct ipc_namespace *
sma->sem_perm.security = NULL;
retval = security_sem_alloc(sma);
if (retval) {
- ipc_rcu_putref(&sma->sem_perm, ipc_rcu_free);
+ __sem_free(sma);
return retval;
}
_
Patches currently in -mm which might be from keescook@xxxxxxxxxxxx are
ipc-drop-non-rcu-allocation.patch
ipc-sem-do-not-use-ipc_rcu_free.patch
ipc-shm-do-not-use-ipc_rcu_free.patch
ipc-msg-do-not-use-ipc_rcu_free.patch
ipc-util-drop-ipc_rcu_free.patch
ipc-sem-avoid-ipc_rcu_alloc.patch
ipc-shm-avoid-ipc_rcu_alloc.patch
ipc-msg-avoid-ipc_rcu_alloc.patch
ipc-util-drop-ipc_rcu_alloc.patch
ipc-move-atomic_set-to-where-it-is-needed.patch
ipc-shm-remove-special-shm_alloc-free.patch
ipc-msg-remove-special-msg_alloc-free.patch
ipc-sem-drop-__sem_free.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
