David Herrmann 47191d65b6 netlink: fix locking around NETLINK_LIST_MEMBERSHIPS ... Currently, NETLINK_LIST_MEMBERSHIPS grabs the netlink table while copying the membership state to user-space. However, grabing the netlink table is effectively a write_lock_irq(), and as such we should not be triggering page-faults in the critical section. This can be easily reproduced by the following snippet: int s = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); void *p = mmap(0, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0); int r = getsockopt(s, 0x10e, 9, p, (void*)((char*)p + 4092)); This should work just fine, but currently triggers EFAULT and a possible WARN_ON below handle_mm_fault(). Fix this by reducing locking of NETLINK_LIST_MEMBERSHIPS to a read-side lock. The write-lock was overkill in the first place, and the read-lock allows page-faults just fine. Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2015-10-22 07:18:28 -07:00
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af_netlink.c	netlink: fix locking around NETLINK_LIST_MEMBERSHIPS	2015-10-22 07:18:28 -07:00
af_netlink.h	netlink: Replace rhash_portid with bound	2015-09-24 12:07:08 -07:00
diag.c	netlink: make nlmsg_end() and genlmsg_end() void	2015-01-18 01:03:45 -05:00
genetlink.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2015-01-27 16:59:56 -08:00
Kconfig	netlink: kconfig: move mmap i/o into netlink kconfig	2013-05-01 15:02:42 -04:00
Makefile	netlink: Diag core and basic socket info dumping (v2)	2013-03-21 12:38:03 -04:00