Kirill A. Shutemov 23f1538b9c mm: Fix NULL pointer dereference in madvise(MADV_WILLNEED) support ... commit ee53664bda upstream. Sasha Levin found a NULL pointer dereference that is due to a missing page table lock, which in turn is due to the pmd entry in question being a transparent huge-table entry. The code - introduced in commit 1998cc0489 ("mm: make madvise(MADV_WILLNEED) support swap file prefetch") - correctly checks for this situation using pmd_none_or_trans_huge_or_clear_bad(), but it turns out that that function doesn't work correctly. pmd_none_or_trans_huge_or_clear_bad() expected that pmd_bad() would trigger if the transparent hugepage bit was set, but it doesn't do that if pmd_numa() is also set. Note that the NUMA bit only gets set on real NUMA machines, so people trying to reproduce this on most normal development systems would never actually trigger this. Fix it by removing the very subtle (and subtly incorrect) expectation, and instead just checking pmd_trans_huge() explicitly. Reported-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Andrea Arcangeli <aarcange@redhat.com> [ Additionally remove the now stale test for pmd_trans_huge() inside the pmd_bad() case - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Wang Long <long.wanglong@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2015-04-29 10:33:58 +02:00
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acpi	ACPI / hotplug: Fix conflicted PCI bridge notify handlers	2013-12-04 10:57:04 -08:00
asm-generic	mm: Fix NULL pointer dereference in madvise(MADV_WILLNEED) support	2015-04-29 10:33:58 +02:00
clocksource	clocksource: arch_timer: use virtual counters	2014-01-09 12:24:26 -08:00
crypto	crypto: scatterwalk - Use sg_chain_ptr on chain entries	2013-12-11 22:36:29 -08:00
drm	drm/radeon: remove invalid pci id	2014-11-14 08:48:00 -08:00
dt-bindings
keys
linux	remove extra definitions of U32_MAX	2015-04-29 10:33:54 +02:00
math-emu
media	media: vb2: fix VBI/poll regression	2014-10-09 12:18:42 -07:00
memory
misc
net	ipv4: tcp: get rid of ugly unicast_sock	2015-02-26 17:48:48 -08:00
pcmcia
ras
rdma
rxrpc
scsi	scsi: fix our current target reap infrastructure	2014-05-30 21:52:11 -07:00
sound	ALSA: ak411x: Fix stall in work callback	2015-02-11 14:48:17 +08:00
target	target: Report correct response length for some commands	2014-06-30 20:09:45 -07:00
trace	tracing: Fix syscall_*regfunc() vs copy_process() race	2014-07-06 18:54:16 -07:00
uapi	netfilter: xt_bpf: add mising opaque struct sk_filter definition	2014-11-21 09:22:54 -08:00
video	Merge branch 'fbdev-3.10-fixes' of git://gitorious.org/linux-omap-dss2/linux into linux-fbdev/for-3.10-fixes	2013-05-29 17:00:34 +08:00
xen	xenbus: delay xenbus frontend resume if xenstored is not running	2013-05-29 09:04:19 -04:00
Kbuild	UAPI: remove empty Kbuild files	2013-04-30 17:04:09 -07:00