When the new signal handlers are set up, the location of sa_restorer is
not cleared, leaking a parent process's address space location to
children. This allows for a potential bypass of the parent's ASLR by
examining the sa_restorer value returned when calling sigaction().
Based on what should be considered "secret" about addresses, it only
matters across the exec not the fork (since the VMAs haven't changed
until the exec). But since exec sets SIG_DFL and keeps sa_restorer,
this is where it should be fixed.
Given the few uses of sa_restorer, a "set" function was not written
since this would be the only use. Instead, we use
__ARCH_HAS_SA_RESTORER, as already done in other places.
Example of the leak before applying this patch:
$ cat /proc/$$/maps
...
7fb9f3083000-7fb9f3238000 r-xp 00000000 fd:01 404469 .../libc-2.15.so
...
$ ./leak
...
7f278bc74000-7f278be29000 r-xp 00000000 fd:01 404469 .../libc-2.15.so
...
1 0 (nil) 0x7fb9f30b94a0
2 4000000 (nil) 0x7f278bcaa4a0
3 4000000 (nil) 0x7f278bcaa4a0
4 0 (nil) 0x7fb9f30b94a0
...
[akpm@linux-foundation.org: use SA_RESTORER for backportability]
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Emese Revfy <re.emese@gmail.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Julien Tinnes <jln@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
alpha allmodconfig:
In file included from mm/memcontrol.c:28:
include/linux/res_counter.h: In function 'res_counter_set_limit':
include/linux/res_counter.h:203: error: 'EBUSY' undeclared (first use in this function)
include/linux/res_counter.h:203: error: (Each undeclared identifier is reported only once
include/linux/res_counter.h:203: error: for each function it appears in.)
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix kernel-doc warning in futex.c and convert 'Returns' to the new Return:
kernel-doc notation format.
Warning(kernel/futex.c:2286): Excess function parameter 'clockrt' description in 'futex_wait_requeue_pi'
Fix one spello.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix new kernel-doc warnings in kernel/signal.c:
Warning(kernel/signal.c:2689): No description found for parameter 'uset'
Warning(kernel/signal.c:2689): Excess function parameter 'set' description in 'sys_rt_sigpending'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix new kernel-doc warnings in idr:
Warning(include/linux/idr.h:113): No description found for parameter 'idr'
Warning(include/linux/idr.h:113): Excess function parameter 'idp' description in 'idr_find'
Warning(lib/idr.c:232): Excess function parameter 'id' description in 'sub_alloc'
Warning(lib/idr.c:232): Excess function parameter 'id' description in 'sub_alloc'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull Xen fixes from Konrad Rzeszutek Wilk:
- Compile warnings and errors (one on x86, two on ARM)
- WARNING in xen-pciback
- Use the acpi_processor_get_performance_info instead of the 'register'
version
* tag 'stable/for-linus-3.9-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/acpi: remove redundant acpi/acpi_drivers.h include
xen: arm: mandate EABI and use generic atomic operations.
acpi: Export the acpi_processor_get_performance_info
xen/pciback: Don't disable a PCI device that is already disabled.
In commit 887cbce0ad ("arch Kconfig: centralise ARCH_NO_VIRT_TO_BUS")
I introduced the config sybmol HAVE_VIRT_TO_BUS and selected that where
needed. I am not sure what I was thinking. Instead, just directly
select VIRT_TO_BUS where it is needed.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Looking at mm/process_vm_access.c:process_vm_rw() and comparing it to
compat_process_vm_rw() shows that the compatibility code requires an
explicit "access_ok()" check before calling
compat_rw_copy_check_uvector(). The same difference seems to appear when
we compare fs/read_write.c:do_readv_writev() to
fs/compat.c:compat_do_readv_writev().
This subtle difference between the compat and non-compat requirements
should probably be debated, as it seems to be error-prone. In fact,
there are two others sites that use this function in the Linux kernel,
and they both seem to get it wrong:
Now shifting our attention to fs/aio.c, we see that aio_setup_iocb()
also ends up calling compat_rw_copy_check_uvector() through
aio_setup_vectored_rw(). Unfortunately, the access_ok() check appears to
be missing. Same situation for
security/keys/compat.c:compat_keyctl_instantiate_key_iov().
I propose that we add the access_ok() check directly into
compat_rw_copy_check_uvector(), so callers don't have to worry about it,
and it therefore makes the compat call code similar to its non-compat
counterpart. Place the access_ok() check in the same location where
copy_from_user() can trigger a -EFAULT error in the non-compat code, so
the ABI behaviors are alike on both compat and non-compat.
While we are here, fix compat_do_readv_writev() so it checks for
compat_rw_copy_check_uvector() negative return values.
And also, fix a memory leak in compat_keyctl_instantiate_key_iov() error
handling.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull drm nouveau fixes from Dave Airlie:
"This is just nouveau fixes from Ben, one fixes a nasty oops that some
Fedora people have been seeing, so I'd like to get it out of the way."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/nv50: use correct tiling methods for m2mf buffer moves
drm/nouveau: idle channel before releasing notify object
drm/nouveau: fix regression in vblanking
drm/nv50: encoder creation failure doesn't mean full init failure
Pull ARM SoC fixes from Arnd Bergmann:
"These bug fixes are for the largest part for mvebu/kirkwood, which saw
a few regressions after the clock infrastructure was enabled, and for
OMAP, which showed a few more preexisting bugs with the new
multiplatform support.
Other small fixes are for imx, mxs, tegra, spear and socfpga"
* tag 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (37 commits)
ARM: spear3xx: Use correct pl080 header file
Arm: socfpga: pl330: Add #dma-cells for generic dma binding support
ARM: multiplatform: Sort the max gpio numbers.
ARM: imx: fix typo "DEBUG_IMX50_IMX53_UART"
ARM: imx: pll1_sys should be an initial on clk
arm: mach-orion5x: fix typo in compatible string of a .dts file
arm: mvebu: fix address-cells in mpic DT node
arm: plat-orion: fix address decoding when > 4GB is used
arm: mvebu: Reduce reg-io-width with UARTs
ARM: Dove: add RTC device node
arm: mvebu: enable the USB ports on Armada 370 Reference Design board
ARM: dove: drop "select COMMON_CLK_DOVE"
rtc: rtc-mv: Add support for clk to avoid lockups
gpio: mvebu: Add clk support to prevent lockup
ARM: kirkwood: fix to retain gbe MAC addresses for DT kernels
ARM: kirkwood: of_serial: fix clock gating by removing clock-frequency
ARM: mxs: cfa10049: Fix fb initialisation function
ARM: SPEAr13xx: Fix typo "ARCH_HAVE_CPUFREQ"
ARM: OMAP: RX-51: add missing USB phy binding
clk: Tegra: Remove duplicate smp_twd clock
...
Pull m68knommu fixes from Greg Ungerer:
"It contains a few small fixes for the non-MMU m68k platforms. Fixes
some compilation problems, some broken header definitions, removes an
unused config option and adds a name for the old 68000 CPU support."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68k: drop "select EMAC_INC"
m68knommu: fix misnamed GPIO pin definition for ColdFire 528x CPU
m68knommu: fix MC68328.h defines
m68knommu: fix build when CPU is not coldfire
m68knommu: add CPU_NAME for 68000
Pull key management race fix from James Morris.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
keys: fix race with concurrent install_user_keyrings()
Pull Ceph fix from Sage Weil:
"This fixes a bug in the new message decoding that just went in during
the last window."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: fix decoding of pgids
Pull nfsd bugfixes from Bruce Fields:
"Some minor fallout from the user-namespace work broke most krb5 mounts
to nfsd, and I screwed up a change to the AF_LOCAL rpc code."
* 'for-3.9' of git://linux-nfs.org/~bfields/linux:
sunrpc: don't attempt to cancel unitialized work
nfsd: fix krb5 handling of anonymous principals
If you open a pipe for neither read nor write, the pipe code will not
add any usage counters to the pipe, causing the 'struct pipe_inode_info"
to be potentially released early.
That doesn't normally matter, since you cannot actually use the pipe,
but the pipe release code - particularly fasync handling - still expects
the actual pipe infrastructure to all be there. And rather than adding
NULL pointer checks, let's just disallow this case, the same way we
already do for the named pipe ("fifo") case.
This is ancient going back to pre-2.4 days, and until trinity, nobody
naver noticed.
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The definitions have move around recently, causing build errors
in spear3xx for all configurations:
spear3xx.c:47:5: error: 'PL080_BSIZE_16' undeclared here (not in a function)
spear3xx.c:47:23: error: 'PL080_CONTROL_SB_SIZE_SHIFT' undeclared here (not in a function)
spear3xx.c:48:22: error: 'PL080_CONTROL_DB_SIZE_SHIFT' undeclared here (not in a function)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alessandro Rubini <rubini@gnudd.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
This fixes CVE-2013-1792.
There is a race in install_user_keyrings() that can cause a NULL pointer
dereference when called concurrently for the same user if the uid and
uid-session keyrings are not yet created. It might be possible for an
unprivileged user to trigger this by calling keyctl() from userspace in
parallel immediately after logging in.
Assume that we have two threads both executing lookup_user_key(), both
looking for KEY_SPEC_USER_SESSION_KEYRING.
THREAD A THREAD B
=============================== ===============================
==>call install_user_keyrings();
if (!cred->user->session_keyring)
==>call install_user_keyrings()
...
user->uid_keyring = uid_keyring;
if (user->uid_keyring)
return 0;
<==
key = cred->user->session_keyring [== NULL]
user->session_keyring = session_keyring;
atomic_inc(&key->usage); [oops]
At the point thread A dereferences cred->user->session_keyring, thread B
hasn't updated user->session_keyring yet, but thread A assumes it is
populated because install_user_keyrings() returned ok.
The race window is really small but can be exploited if, for example,
thread B is interrupted or preempted after initializing uid_keyring, but
before doing setting session_keyring.
This couldn't be reproduced on a stock kernel. However, after placing
systemtap probe on 'user->session_keyring = session_keyring;' that
introduced some delay, the kernel could be crashed reliably.
Fix this by checking both pointers before deciding whether to return.
Alternatively, the test could be done away with entirely as it is checked
inside the mutex - but since the mutex is global, that may not be the best
way.
Signed-off-by: David Howells <dhowells@redhat.com>
Reported-by: Mateusz Guzik <mguzik@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
In 4f6a7e5ee1 we effectively dropped support
for the legacy encoding for the OSDMap and incremental. However, we didn't
fix the decoding for the pgid.
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
This patch adds #dma-cells property to PL330 DMA controller nodes for
supporting generic dma dt bindings on SOCFPGA platform. #dma-channels
and #dma-requests are not required now but added in advance.
Signed-off-by: Padmavathi Venna <padma.v@samsung.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
mvebu fixes for v3.9 from Jason Cooper <jason@lakedaemon.net>:
The first four patches:
89c58c1 rtc: rtc-mv: Add support for clk to avoid lockups
de88747 gpio: mvebu: Add clk support to prevent lockup
7bf5b40 ARM: kirkwood: fix to retain gbe MAC addresses for DT kernels
93fff4c ARM: kirkwood: of_serial: fix clock gating by removing clock-frequency
are Cc'd to stable since they were held over from the previous merge window.
The rest are a small collection of fixes and a couple of devicetree conversion
catchups.
* tag 'mvebu_fixes_for_v3.9' of git://git.infradead.org/users/jcooper/linux:
arm: mach-orion5x: fix typo in compatible string of a .dts file
arm: mvebu: fix address-cells in mpic DT node
arm: plat-orion: fix address decoding when > 4GB is used
arm: mvebu: Reduce reg-io-width with UARTs
ARM: Dove: add RTC device node
arm: mvebu: enable the USB ports on Armada 370 Reference Design board
ARM: dove: drop "select COMMON_CLK_DOVE"
rtc: rtc-mv: Add support for clk to avoid lockups
gpio: mvebu: Add clk support to prevent lockup
ARM: kirkwood: fix to retain gbe MAC addresses for DT kernels
ARM: kirkwood: of_serial: fix clock gating by removing clock-frequency
Signed-off-by: Arnd Bergmann <arnd@arndb.de>