Messages in this thread Patch in this message | | | From | Jia-Ju Bai <> | Subject | [PATCH] block/drbd: Fix a sleep-in-atomic bug in drbd_bcast_event | Date | Wed, 4 Oct 2017 09:33:18 +0800 |
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The driver may sleep under a RCU lock, and the function call path is: drbd_sync_handshake (acquire the RCU lock) drbd_asb_recover_1p drbd_khelper drbd_bcast_event genlmsg_new(GFP_NOIO) --> may sleep
To fix it, GFP_NOIO is replaced with GFP_ATOMIC. This bug is found by my static analysis tool and my code review.
Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com> --- drivers/block/drbd/drbd_nl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index a12f77e..713c965 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -4537,7 +4537,7 @@ void drbd_bcast_event(struct drbd_device *device, const struct sib_info *sib) int err = -ENOMEM; seq = atomic_inc_return(&drbd_genl_seq); - msg = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO); + msg = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC); if (!msg) goto failed; -- 1.7.9.5
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