Kees Cook
f06295b44c
ELF: implement AT_RANDOM for glibc PRNG seeding ...
While discussing[1] the need for glibc to have access to random bytes
during program load, it seems that an earlier attempt to implement
AT_RANDOM got stalled. This implements a random 16 byte string, available
to every ELF program via a new auxv AT_RANDOM vector.
[1] http://sourceware.org/ml/libc-alpha/2008-10/msg00006.html
Ulrich said:
glibc needs right after startup a bit of random data for internal
protections (stack canary etc). What is now in upstream glibc is that we
always unconditionally open /dev/urandom, read some data, and use it. For
every process startup. That's slow.
...
The solution is to provide a limited amount of random data to the
starting process in the aux vector. I suggested 16 bytes and this is
what the patch implements. If we need only 16 bytes or less we use the
data directly. If we need more we'll use the 16 bytes to see a PRNG.
This avoids the costly /dev/urandom use and it allows the kernel to use
the most adequate source of random data for this purpose. It might not
be the same pool as that for /dev/urandom.
Concerns were expressed about the depletion of the randomness pool. But
this patch doesn't make the situation worse, it doesn't deplete entropy
more than happens now.
Signed-off-by: Kees Cook <kees.cook@canonical.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-08 08:31:12 -08:00
byteorder: only use linux/swab.h
2009-01-06 18:10:26 -08:00
V4L/DVB (10166): dvb frontend: stop using non-C99 compliant comments
2009-01-02 17:15:07 -02:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
2009-01-06 17:14:01 -08:00
NLM: Rewrite IPv4 privileged requester's check
2009-01-06 11:53:56 -05:00
mfd: Add WM8351 support
2009-01-04 12:17:42 +01:00
mmc: Add mmc_vddrange_to_ocrmask() helper function
2008-12-31 18:18:13 +01:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
2009-01-07 11:31:52 -08:00
nfsd: get rid of NFSD_VERSION
2009-01-07 17:38:32 -05:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
2009-01-07 11:31:52 -08:00
sunrpc: add sv_maxconn field to svc_serv (try #3 )
2009-01-06 11:53:47 -05:00
USB: musb: use new platform data interface of musb to replace old one
2009-01-07 10:00:06 -08:00
wimax: export linux/wimax.h and linux/wimax/i2400m.h with headers_install
2009-01-07 10:00:22 -08:00
And here's a patch (to be applied on top of the last) which prevents
2009-01-02 10:19:37 -08:00
aio: make the lookup_ioctx() lockless
2008-12-29 08:29:50 +01:00
async: Asynchronous function calls to speed up kernel boot
2009-01-07 08:45:46 -08:00
atmel-mci: move atmel-mci.h file to include/linux
2009-01-05 16:35:31 +01:00
audit: validate comparison operations, store them in sane form
2009-01-04 15:14:42 -05:00
autofs4: improve parameter usage
2009-01-06 15:59:23 -08:00
autofs4: make autofs type usage explicit
2009-01-06 15:59:23 -08:00
ELF: implement AT_RANDOM for glibc PRNG seeding
2009-01-08 08:31:12 -08:00
fs/exec.c: make do_coredump() void
2009-01-06 15:59:29 -08:00
bio: add support for inlining a number of bio_vecs inside the bio
2008-12-29 08:29:50 +01:00
bitmap: test for constant as well as small size for inline versions
2008-12-30 09:05:13 +10:30
bitmap: find_last_bit()
2009-01-01 10:12:19 +10:30
block: get rid of elevator_t typedef
2008-12-29 08:29:50 +01:00
fs: introduce bgl_lock_ptr()
2009-01-04 13:33:20 -08:00
CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #3 ]
2009-01-07 09:38:48 +11:00
cgroups: add css_tryget()
2009-01-08 08:31:10 -08:00
Sanitize gcc version header includes
2009-01-02 09:23:03 -08:00
Disallow gcc versions 3.{0,1}
2009-01-02 12:19:34 -08:00
Disallow gcc versions 4.1.{0,1}
2009-01-02 09:29:43 -08:00
Sanitize gcc version header includes
2009-01-02 09:23:03 -08:00
DRM: add mode setting support
2008-12-29 17:47:23 +10:00
cpumask: CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
2009-01-01 10:12:30 +10:30
cpuset: remove remaining pointers to cpumask_t
2009-01-08 08:31:11 -08:00
shrink struct dentry
2008-12-31 18:07:38 -05:00
debugfs: add helpers for exporting a size_t simple value
2009-01-07 10:00:16 -08:00
dm: support barriers on simple devices
2009-01-06 03:05:09 +00:00
driver core: add root_device_register()
2009-01-06 10:44:33 -08:00
intel-iommu: fix build error with INTR_REMAP=y and DMAR=n
2009-01-04 11:00:05 +01:00
intel-iommu: kill off duplicate def of dmar_disabled
2009-01-03 11:57:35 +01:00
DMI: add dmi_match
2008-12-29 07:39:34 -05:00
quota: Split off quota tree handling into a separate file
2009-01-05 08:40:21 -08:00
quota: Unexport dqblk_v1.h and dqblk_v2.h
2009-01-05 08:40:25 -08:00
quota: Unexport dqblk_v1.h and dqblk_v2.h
2009-01-05 08:40:25 -08:00
block: get rid of elevator_t typedef
2008-12-29 08:29:50 +01:00
ext2: tighten restrictions on inode flags
2009-01-08 08:31:00 -08:00
ext2: allocate ->s_blockgroup_lock separately
2009-01-08 08:31:00 -08:00
ext3: tighten restrictions on inode flags
2009-01-08 08:31:01 -08:00
ext3: allocate ->s_blockgroup_lock separately
2009-01-08 08:31:00 -08:00
SLUB: failslab support
2008-12-29 11:27:46 +02:00
filp_cachep can be static in fs/file_table.c
2008-12-31 18:07:42 -05:00
async: make the final inode deletion an asynchronous event
2009-01-07 08:47:24 -08:00
take init_fs to saner place
2008-12-31 18:07:42 -05:00
tty_port: Add a port level carrier detect operation
2009-01-02 10:19:38 -08:00
block: add one-hit cache for disk partition lookup
2008-12-29 08:29:51 +01:00
mm: remove GFP_HIGHUSER_PAGECACHE
2009-01-06 15:59:01 -08:00
Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-30 16:10:19 -08:00
HID: avoid sparse warning in HID_COMPAT_LOAD_DRIVER
2009-01-04 01:00:53 +01:00
HID: add phys and name ioctls to hidraw
2009-01-04 01:00:51 +01:00
mm: report the MMU pagesize in /proc/pid/smaps
2009-01-06 15:58:58 -08:00
i2c: Drop I2C_CLASS_CAM_DIGITAL
2009-01-07 14:29:17 +01:00
ide: move read_sff_dma_status() method to 'struct ide_dma_ops'
2009-01-06 17:21:02 +01:00
take init_fs to saner place
2008-12-31 18:07:42 -05:00
VT-d: remove now unused intel_iommu_found function
2009-01-03 14:11:08 +01:00
Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-01-06 17:10:53 -08:00
introcude linux/iommu.h for an iommu api
2009-01-03 14:10:09 +01:00
resource: allow MMIO exclusivity for device drivers
2009-01-07 11:12:32 -08:00
Merge branch 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-01-02 11:44:09 -08:00
genirq: provide irq_to_desc() to non-genirq architectures too
2009-01-05 14:53:30 +01:00
tty: Introduce some close helpers for ports
2009-01-02 10:19:40 -08:00
jbd: improve fsync batching
2009-01-08 08:31:00 -08:00
jbd2: Add buffer triggers
2009-01-05 08:40:30 -08:00
jbd2: Add buffer triggers
2009-01-05 08:40:30 -08:00
wimax: export linux/wimax.h and linux/wimax/i2400m.h with headers_install
2009-01-07 10:00:22 -08:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
2009-01-06 17:02:07 -08:00
[PATCH] idle cputime accounting
2008-12-31 15:11:46 +01:00
driver core: Remove completion from struct klist_node
2009-01-06 10:44:30 -08:00
kprobes: support probing module __exit function
2009-01-06 15:59:21 -08:00
KVM: x86: Rework user space NMI injection as KVM_CAP_USER_NMI
2008-12-31 16:55:47 +02:00
KVM: change KVM to use IOMMU API
2009-01-03 14:11:07 +01:00
lguest: move the initial guest page table creation code to the host
2008-12-30 09:26:11 +10:30
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-30 16:20:19 -08:00
xen: add xenfs to allow usermode <-> Xen interaction
2009-01-08 08:30:59 -08:00
Input: map_to_7segment.h - convert to __inline__ for userspace
2008-12-29 04:59:31 -08:00
memcg: fix shmem's swap accounting
2009-01-08 08:31:10 -08:00
mm: show node to memory section relationship with symlinks in sysfs
2009-01-06 15:59:00 -08:00
mm: show node to memory section relationship with symlinks in sysfs
2009-01-06 15:59:00 -08:00
mm: cleanup: remove #ifdef CONFIG_MIGRATION
2009-01-06 15:59:00 -08:00
mm: invoke oom-killer from page fault
2009-01-06 15:58:58 -08:00
inactive_anon_is_low: move to vmscan
2009-01-08 08:31:07 -08:00
aio: make the lookup_ioctx() lockless
2008-12-29 08:29:50 +01:00
mm: introduce zone_reclaim struct
2009-01-08 08:31:07 -08:00
module: add within_module_core() and within_module_init()
2009-01-06 15:59:20 -08:00
module: fix module loading failure of large kernel modules for parisc
2009-01-05 08:40:13 +10:30
vfs: introduce helper function to safely NUL-terminate symlinks
2008-12-31 18:07:38 -05:00
trivial: fix an -> a typos in documentation and comments
2009-01-06 11:28:07 +01:00
gro: Add page frag support
2009-01-04 16:13:40 -08:00
nfsd: last_byte_offset
2009-01-07 17:38:31 -05:00
mm: show node to memory section relationship with symlinks in sysfs
2009-01-06 15:59:00 -08:00
usb host: Oxford OXU210HP HCD driver.
2009-01-07 09:59:50 -08:00
badpage: simplify page_alloc flag check+clear
2009-01-06 15:59:07 -08:00
memcg: synchronized LRU
2009-01-08 08:31:05 -08:00
fs: symlink write_begin allocation context fix
2009-01-04 13:33:20 -08:00
mm: get rid of pagevec_release_nonlru()
2009-01-06 15:59:00 -08:00
PCI hotplug: introduce functions for ACPI slot detection
2009-01-07 11:13:11 -08:00
x86/PCI: Do not use interrupt links for devices using MSI-X
2009-01-07 11:13:25 -08:00
PCI hotplug: introduce functions for ACPI slot detection
2009-01-07 11:13:11 -08:00
Resurrect IT8172 IDE controller driver
2009-01-06 17:21:01 +01:00
PCI: pciehp: cleanup register and field definitions
2009-01-07 11:13:22 -08:00
Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-01-06 17:10:04 -08:00
pid: implement ns_of_pid
2009-01-08 08:31:12 -08:00
pid: generalize task_active_pid_ns
2009-01-08 08:31:12 -08:00
PM: Simplify the new suspend/hibernation framework for devices
2009-01-06 10:44:29 -08:00
Fix misspellings in pm.h macros
2009-01-06 10:44:30 -08:00
poll: allow f_op->poll to sleep
2009-01-06 15:59:12 -08:00
power_supply: Add cold to the POWER_SUPPLY_HEALTH report values
2009-01-04 12:17:39 +01:00
qnx: include <linux/types.h> for definitions of __[us]{8,16,32,64} types
2009-01-07 21:44:20 +01:00
qnx: include <linux/types.h> for definitions of __[us]{8,16,32,64} types
2009-01-07 21:44:20 +01:00
quota: Unexport dqblk_v1.h and dqblk_v2.h
2009-01-05 08:40:25 -08:00
quota: Export dquot_alloc() and dquot_destroy() functions
2009-01-05 08:40:25 -08:00
mm lockless pagecache barrier fix
2009-01-05 18:31:12 -08:00
sparseirq: move set/get_timer_rand_state back to .c
2009-01-03 12:01:23 -08:00
cpumask: convert RCU implementations
2009-01-01 10:12:26 +10:30
rcu: eliminate synchronize_rcu_xxx macro
2009-01-05 10:18:08 +01:00
memcg: memory cgroup resource counters for hierarchy
2009-01-08 08:31:05 -08:00
Merge branch 'oprofile-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-30 17:31:25 -08:00
rapidio: remove excess kernel-doc notation
2009-01-06 15:59:28 -08:00
badpage: remove vma from page_remove_rmap
2009-01-06 15:59:07 -08:00
rtc: add alarm/update irq interfaces
2009-01-04 13:33:20 -08:00
Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-01-06 17:10:33 -08:00
Merge branch 'next' into for-linus
2009-01-07 09:58:22 +11:00
cpumask: Use nr_cpu_ids in seq_cpumask
2008-12-30 09:05:19 +10:30
serial: RS485 ioctl structure uses __u32 include linux/types.h
2009-01-02 10:19:42 -08:00
Serial: Allow port type to be specified when calling serial8250_register_port.
2009-01-02 10:19:43 -08:00
Serial: UART driver changes for Cavium OCTEON.
2009-01-02 10:19:43 -08:00
Merge branches 'topic/fixes', 'topic/cleanups' and 'topic/documentation' into for-linus
2008-12-29 11:45:47 +02:00
cpumask: smp_call_function_many()
2008-12-30 09:05:16 +10:30
stop_machine: introduce stop_machine_create/destroy.
2009-01-05 08:40:14 +10:30
Fix up 64-bit byte swaps for most 32-bit architectures
2009-01-06 21:17:57 -08:00
memcg: fix shmem's swap accounting
2009-01-08 08:31:10 -08:00
inotify: fix type errors in interfaces
2009-01-05 11:54:29 -05:00
cpumask: make CONFIG_NR_CPUS always valid.
2008-12-30 09:05:12 +10:30
cpumask: convert kernel time functions
2009-01-01 10:12:25 +10:30
sched_clock: prevent scd->clock from moving backwards, take #2
2008-12-31 09:53:21 +01:00
tty: Introduce some close helpers for ports
2009-01-02 10:19:40 -08:00
pty: simplify resize
2009-01-02 10:19:36 -08:00
linux/types.h: Don't depend on __GNUC__ for __le64/__be64
2009-01-07 11:27:12 -08:00
uio: make uio_info's name and version const
2009-01-06 10:44:44 -08:00
USB: remove info() macro from usb.h
2009-01-07 10:00:14 -08:00
USB: storage: add last-sector hacks
2009-01-07 10:00:11 -08:00
V4L/DVB (10141): v4l2: debugging API changed to match against driver name instead of ID.
2009-01-02 17:11:52 -02:00
virtio: avoid implicit use of Linux page size in balloon interface
2008-12-30 09:26:04 +10:30
virtio_console: support console resizing
2008-12-30 09:26:10 +10:30
virtio: Don't use PAGE_SIZE for vring alignment in virtio_pci.
2008-12-30 09:25:58 +10:30
virtio: hand virtio ring alignment as argument to vring_new_virtqueue
2008-12-30 09:26:03 +10:30
mm: make vread() and vwrite() declaration
2009-01-06 15:59:05 -08:00
wimax: headers for kernel API and user space interaction
2009-01-07 10:00:16 -08:00
fs: remove WB_SYNC_HOLD
2009-01-06 15:59:09 -08:00
