kernel_optimize_test/lib
David Howells 23fd78d764 KEYS: Fix multiple key add into associative array
If sufficient keys (or keyrings) are added into a keyring such that a node in
the associative array's tree overflows (each node has a capacity N, currently
16) and such that all N+1 keys have the same index key segment for that level
of the tree (the level'th nibble of the index key), then assoc_array_insert()
calls ops->diff_objects() to indicate at which bit position the two index keys
vary.

However, __key_link_begin() passes a NULL object to assoc_array_insert() with
the intention of supplying the correct pointer later before we commit the
change.  This means that keyring_diff_objects() is given a NULL pointer as one
of its arguments which it does not expect.  This results in an oops like the
attached.

With the previous patch to fix the keyring hash function, this can be forced
much more easily by creating a keyring and only adding keyrings to it.  Add any
other sort of key and a different insertion path is taken - all 16+1 objects
must want to cluster in the same node slot.

This can be tested by:

	r=`keyctl newring sandbox @s`
	for ((i=0; i<=16; i++)); do keyctl newring ring$i $r; done

This should work fine, but oopses when the 17th keyring is added.

Since ops->diff_objects() is always called with the first pointer pointing to
the object to be inserted (ie. the NULL pointer), we can fix the problem by
changing the to-be-inserted object pointer to point to the index key passed
into assoc_array_insert() instead.

Whilst we're at it, we also switch the arguments so that they are the same as
for ->compare_object().

BUG: unable to handle kernel NULL pointer dereference at 0000000000000088
IP: [<ffffffff81191ee4>] hash_key_type_and_desc+0x18/0xb0
...
RIP: 0010:[<ffffffff81191ee4>] hash_key_type_and_desc+0x18/0xb0
...
Call Trace:
 [<ffffffff81191f9d>] keyring_diff_objects+0x21/0xd2
 [<ffffffff811f09ef>] assoc_array_insert+0x3b6/0x908
 [<ffffffff811929a7>] __key_link_begin+0x78/0xe5
 [<ffffffff81191a2e>] key_create_or_update+0x17d/0x36a
 [<ffffffff81192e0a>] SyS_add_key+0x123/0x183
 [<ffffffff81400ddb>] tracesys+0xdd/0xe2

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Stephen Gallagher <sgallagh@redhat.com>
2013-12-02 11:24:18 +00:00
..
fonts
lz4
lzo
mpi
raid6
reed_solomon
xz
zlib_deflate
zlib_inflate
.gitignore
argv_split.c
asn1_decoder.c
assoc_array.c KEYS: Fix multiple key add into associative array 2013-12-02 11:24:18 +00:00
atomic64_test.c
atomic64.c
audit.c
average.c
bcd.c
bch.c
bitmap.c
bitrev.c
bsearch.c
btree.c
bug.c
build_OID_registry
bust_spinlocks.c
check_signature.c
checksum.c
clz_ctz.c
clz_tab.c
cmdline.c
cordic.c
cpu_rmap.c
cpu-notifier-error-inject.c
cpumask.c
crc7.c
crc8.c
crc16.c
crc32.c
crc32defs.h
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c
ctype.c
debug_locks.c
debugobjects.c
dec_and_lock.c
decompress_bunzip2.c
decompress_inflate.c
decompress_unlz4.c
decompress_unlzma.c
decompress_unlzo.c
decompress_unxz.c
decompress.c
devres.c
digsig.c
div64.c
dma-debug.c
dump_stack.c
dynamic_debug.c
dynamic_queue_limits.c
earlycpio.c
extable.c
fault-inject.c
fdt_ro.c
fdt_rw.c
fdt_strerror.c
fdt_sw.c
fdt_wip.c
fdt.c
find_last_bit.c
find_next_bit.c
flex_array.c
flex_proportions.c
gcd.c
gen_crc32table.c
genalloc.c
halfmd4.c
hexdump.c
hweight.c
idr.c
inflate.c
int_sqrt.c
interval_tree_test_main.c
interval_tree.c
iomap_copy.c
iomap.c
iommu-helper.c
ioremap.c
iovec.c
irq_regs.c
is_single_threaded.c
jedec_ddr_data.c
kasprintf.c
Kconfig Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2013-11-21 19:46:00 -08:00
Kconfig.debug
Kconfig.kgdb
Kconfig.kmemcheck
kfifo.c kfifo: kfifo_copy_{to,from}_user: fix copied bytes calculation 2013-11-15 09:32:23 +09:00
klist.c
kobject_uevent.c
kobject.c
kstrtox.c
kstrtox.h
lcm.c
libcrc32c.c
list_debug.c
list_sort.c
llist.c llists-move-llist_reverse_order-from-raid5-to-llistc-fix 2013-11-15 09:32:22 +09:00
locking-selftest-hardirq.h
locking-selftest-mutex.h
locking-selftest-rlock-hardirq.h
locking-selftest-rlock-softirq.h
locking-selftest-rlock.h
locking-selftest-rsem.h
locking-selftest-softirq.h
locking-selftest-spin-hardirq.h
locking-selftest-spin-softirq.h
locking-selftest-spin.h
locking-selftest-wlock-hardirq.h
locking-selftest-wlock-softirq.h
locking-selftest-wlock.h
locking-selftest-wsem.h
locking-selftest.c
lockref.c lockref: include mutex.h rather than reinvent arch_mutex_cpu_relax 2013-11-27 20:37:33 -08:00
lru_cache.c
Makefile Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2013-11-22 10:52:03 -08:00
md5.c
memory-notifier-error-inject.c
memweight.c
net_utils.c
nlattr.c
notifier-error-inject.c
notifier-error-inject.h
of-reconfig-notifier-error-inject.c
oid_registry.c
parser.c
pci_iomap.c
percpu_counter.c
percpu_ida.c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2013-11-22 10:52:03 -08:00
percpu_test.c
percpu-refcount.c
plist.c
pm-notifier-error-inject.c
prio_heap.c
proportions.c
radix-tree.c
random32.c random32: use msecs_to_jiffies for reseed timer 2013-11-14 16:06:02 -05:00
ratelimit.c
rational.c
rbtree_test.c
rbtree.c
reciprocal_div.c
scatterlist.c
sha1.c
show_mem.c
smp_processor_id.c
sort.c
stmp_device.c
string_helpers.c
string.c
strncpy_from_user.c
strnlen_user.c
swiotlb.c
syscall.c
test-kstrtox.c
test-string_helpers.c
textsearch.c
timerqueue.c
ts_bm.c
ts_fsm.c
ts_kmp.c
ucs2_string.c
usercopy.c
uuid.c
vsprintf.c vsprintf: ignore %n again 2013-11-15 09:32:20 +09:00