f56141e3e2
If an attacker can cause a controlled kernel stack overflow, overwriting the restart block is a very juicy exploit target. This is because the restart_block is held in the same memory allocation as the kernel stack. Moving the restart block to struct task_struct prevents this exploit by making the restart_block harder to locate. Note that there are other fields in thread_info that are also easy targets, at least on some architectures. It's also a decent simplification, since the restart code is more or less identical on all architectures. [james.hogan@imgtec.com: metag: align thread_info::supervisor_stack] Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: David Miller <davem@davemloft.net> Acked-by: Richard Weinberger <richard@nod.at> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Steven Miao <realmz6@gmail.com> Cc: Mark Salter <msalter@redhat.com> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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.. | ||
airq.h | ||
appldata.h | ||
asm-offsets.h | ||
atomic.h | ||
barrier.h | ||
bitops.h | ||
bug.h | ||
bugs.h | ||
cache.h | ||
cacheflush.h | ||
ccwdev.h | ||
ccwgroup.h | ||
checksum.h | ||
chpid.h | ||
cio.h | ||
clp.h | ||
cmb.h | ||
cmpxchg.h | ||
compat.h | ||
cpcmd.h | ||
cpu.h | ||
cpu_mf.h | ||
cputime.h | ||
crw.h | ||
css_chars.h | ||
ctl_reg.h | ||
current.h | ||
debug.h | ||
delay.h | ||
device.h | ||
diag.h | ||
dis.h | ||
div64.h | ||
dma-mapping.h | ||
dma.h | ||
eadm.h | ||
ebcdic.h | ||
elf.h | ||
emergency-restart.h | ||
etr.h | ||
exec.h | ||
extmem.h | ||
facility.h | ||
fb.h | ||
fcx.h | ||
ftrace.h | ||
futex.h | ||
hardirq.h | ||
hugetlb.h | ||
hw_irq.h | ||
idals.h | ||
idle.h | ||
io.h | ||
ipl.h | ||
irq.h | ||
irq_regs.h | ||
irqflags.h | ||
isc.h | ||
itcw.h | ||
jump_label.h | ||
Kbuild | ||
kdebug.h | ||
kexec.h | ||
kmap_types.h | ||
kprobes.h | ||
kvm_host.h | ||
kvm_para.h | ||
linkage.h | ||
local.h | ||
local64.h | ||
lowcore.h | ||
mathemu.h | ||
mman.h | ||
mmu.h | ||
mmu_context.h | ||
module.h | ||
mutex.h | ||
nmi.h | ||
os_info.h | ||
page.h | ||
pci.h | ||
pci_clp.h | ||
pci_debug.h | ||
pci_dma.h | ||
pci_insn.h | ||
pci_io.h | ||
percpu.h | ||
perf_event.h | ||
pgalloc.h | ||
pgtable.h | ||
processor.h | ||
ptrace.h | ||
qdio.h | ||
reset.h | ||
runtime_instr.h | ||
rwsem.h | ||
schid.h | ||
sclp.h | ||
scsw.h | ||
seccomp.h | ||
sections.h | ||
segment.h | ||
serial.h | ||
setup.h | ||
sfp-machine.h | ||
sfp-util.h | ||
shmparam.h | ||
signal.h | ||
sigp.h | ||
smp.h | ||
sparsemem.h | ||
spinlock.h | ||
spinlock_types.h | ||
string.h | ||
switch_to.h | ||
syscall.h | ||
sysinfo.h | ||
termios.h | ||
thread_info.h | ||
timex.h | ||
tlb.h | ||
tlbflush.h | ||
topology.h | ||
types.h | ||
uaccess.h | ||
unaligned.h | ||
unistd.h | ||
uprobes.h | ||
user.h | ||
vdso.h | ||
vga.h | ||
vtime.h | ||
vtimer.h | ||
xor.h |