ARM: missing ->mmap_sem around find_vma() in swp_emulate.c
authorAl Viro <viro@ZenIV.linux.org.uk>
Sun, 16 Dec 2012 00:25:57 +0000 (00:25 +0000)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Thu, 20 Dec 2012 10:40:24 +0000 (10:40 +0000)
commit7bf9b7bef881aac820bf1f2e9951a17b09bd7e04
tree6c74611883e16e5cd6548f9dd3278a9f2fadb1e3
parentdad5451a322bb682704f3ab13a558508a83e0b93
ARM: missing ->mmap_sem around find_vma() in swp_emulate.c

find_vma() is *not* safe when somebody else is removing vmas.  Not just
the return value might get bogus just as you are getting it (this instance
doesn't try to dereference the resulting vma), the search itself can get
buggered in rather spectacular ways.  IOW, ->mmap_sem really, really is
not optional here.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/swp_emulate.c