linux-kernel - [PATCH] mm: add a might_sleep_if in dma_pool

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <1285213967-14052-1-git-send-email-dima@android.com>
Date:	Wed, 22 Sep 2010 20:52:47 -0700
From:	Dima Zavin <dima@...roid.com>
To:	linux-kernel@...r.kernel.org
Cc:	linux-mm@...ck.org, Dima Zavin <dima@...roid.com>
Subject: [PATCH] mm: add a might_sleep_if in dma_pool_alloc

Buggy drivers (e.g. fsl_udc) could call dma_pool_alloc from atomic
context with GFP_KERNEL. In most instances, the first pool_alloc_page
call would succeed and the sleeping functions would never be called.
This allowed the buggy drivers to slip through the cracks.

Add a might_sleep_if checking for __GFP_WAIT in flags.

Signed-off-by: Dima Zavin <dima@...roid.com>
---
 mm/dmapool.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/mm/dmapool.c b/mm/dmapool.c
index 3df0637..4df2de7 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -311,6 +311,8 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
 	size_t offset;
 	void *retval;
 
+	might_sleep_if(mem_flags & __GFP_WAIT);
+
 	spin_lock_irqsave(&pool->lock, flags);
  restart:
 	list_for_each_entry(page, &pool->page_list, page_list) {
-- 
1.6.6

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/