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Linus Torvalds 1bd4403d86 unsafe_[get|put]_user: change interface to use a error target label ... When I initially added the unsafe_[get|put]_user() helpers in commit 5b24a7a2aa ("Add 'unsafe' user access functions for batched accesses"), I made the mistake of modeling the interface on our traditional __[get|put]_user() functions, which return zero on success, or -EFAULT on failure. That interface is fairly easy to use, but it's actually fairly nasty for good code generation, since it essentially forces the caller to check the error value for each access. In particular, since the error handling is already internally implemented with an exception handler, and we already use "asm goto" for various other things, we could fairly easily make the error cases just jump directly to an error label instead, and avoid the need for explicit checking after each operation. So switch the interface to pass in an error label, rather than checking the error value in the caller. Best do it now before we start growing more users (the signal handling code in particular would be a good place to use the new interface). So rather than if (unsafe_get_user(x, ptr)) ... handle error .. the interface is now unsafe_get_user(x, ptr, label); where an error during the user mode fetch will now just cause a jump to 'label' in the caller. Right now the actual _implementation_ of this all still ends up being a "if (err) goto label", and does not take advantage of any exception label tricks, but for "unsafe_put_user()" in particular it should be fairly straightforward to convert to using the exception table model. Note that "unsafe_get_user()" is much harder to convert to a clever exception table model, because current versions of gcc do not allow the use of "asm goto" (for the exception) with output values (for the actual value to be fetched). But that is hopefully not a limitation in the long term. [ Also note that it might be a good idea to switch unsafe_get_user() to actually _return_ the value it fetches from user space, but this commit only changes the error handling semantics ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		History 2016-08-08 13:02:01 -07:00
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842
fonts
lz4
lzo	lzo: check for length overrun in variable length encoding.	2014-09-28 11:08:01 +02:00
mpi	lib/mpi: Fix SG miter leak	2016-07-29 18:30:16 +08:00
raid6
reed_solomon
xz
zlib_deflate
zlib_inflate	zlib: clean up some dead code	2014-08-06 18:01:24 -07:00
.gitignore	X.509: Implement simple static OID registry	2012-10-08 13:50:18 +10:30
argv_split.c
asn1_decoder.c
assoc_array.c	assoc_array: don't call compare_object() on a node	2016-04-06 14:06:48 +01:00
atomic64.c
atomic64_test.c	locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()	2016-06-16 10:48:32 +02:00
audit.c	syscalls: implement execveat() system call	2014-12-13 12:42:51 -08:00
bcd.c	usb/core: use bin2bcd() for bcdDevice in RH	2012-09-10 11:13:16 -07:00
bch.c	lib: add shared BCH ECC library	2011-03-11 14:25:50 +00:00
bitmap.c
bitrev.c	ARM: 8187/1: add CONFIG_HAVE_ARCH_BITREVERSE to support rbit instruction	2014-12-22 16:43:06 +00:00
bsearch.c
btree.c
bug.c	lib/bug.c: use common WARN helper	2016-03-17 15:09:34 -07:00
build_OID_registry
bust_spinlocks.c	printk: Provide a wake_up_klogd() off-case	2013-03-22 16:41:20 -07:00
chacha20.c	random: replace non-blocking pool with a Chacha20-based CRNG	2016-07-03 00:57:23 -04:00
check_signature.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
checksum.c
clz_ctz.c
clz_tab.c
cmdline.c
compat_audit.c
cordic.c
cpu-notifier-error-inject.c
cpu_rmap.c	sched/topology: Rename topology_thread_cpumask() to topology_sibling_cpumask()	2015-05-27 15:22:15 +02:00
cpumask.c
crc-ccitt.c	[PATCH] kernel-doc for lib/crc*.c	2006-06-25 10:01:20 -07:00
crc-itu-t.c
crc-t10dif.c
crc7.c
crc8.c	lib: crc8: add new library module providing crc8 algorithm	2011-06-03 15:01:06 -04:00
crc16.c
crc32.c
crc32defs.h
ctype.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
debug_info.c
debug_locks.c	mutex: Add support for wound/wait style locks	2013-06-26 12:10:56 +02:00
debugobjects.c	debugobjects: insulate non-fixup logic related to static obj from fixup callbacks	2016-05-19 19:12:14 -07:00
dec_and_lock.c	lib: reduce the use of module.h wherever possible	2012-03-07 15:04:04 -05:00
decompress.c
decompress_bunzip2.c
decompress_inflate.c	lib/decompressors: use real out buf size for gunzip with kernel	2015-09-10 13:29:01 -07:00
decompress_unlz4.c	lib/decompressors: use real out buf size for gunzip with kernel	2015-09-10 13:29:01 -07:00
decompress_unlzma.c
decompress_unlzo.c
decompress_unxz.c
devres.c
digsig.c
div64.c
dma-debug.c
dma-noop.c	dma-mapping: use unsigned long for dma_attrs	2016-08-04 08:50:07 -04:00
dump_stack.c
dynamic_debug.c
dynamic_queue_limits.c
earlycpio.c	lib/cpio: Make find_cpio_data()'s offset arg optional	2016-06-08 11:04:19 +02:00
extable.c	extable: add support for relative extables to search and sort routines	2016-02-24 14:57:26 +00:00
fault-inject.c	fault-inject: fix inverted interval/probability values in printk	2015-10-23 17:55:10 +09:00
fdt.c	of/lib: Allow scripts/dtc/libfdt to be used from kernel code	2012-07-23 13:54:52 +01:00
fdt_empty_tree.c	lib: add fdt_empty_tree.c	2014-04-30 19:49:37 +01:00
fdt_ro.c
fdt_rw.c
fdt_strerror.c
fdt_sw.c	of/lib: Allow scripts/dtc/libfdt to be used from kernel code	2012-07-23 13:54:52 +01:00
fdt_wip.c	of/lib: Allow scripts/dtc/libfdt to be used from kernel code	2012-07-23 13:54:52 +01:00
find_bit.c
flex_array.c	reciprocal_divide: update/correction of the algorithm	2014-01-21 23:17:20 -08:00
flex_proportions.c
gcd.c	lib/GCD.c: use binary GCD algorithm instead of Euclidean	2016-05-20 17:58:30 -07:00
gen_crc32table.c
genalloc.c
glob.c
halfmd4.c
hexdump.c
hweight.c
idr.c
inflate.c	MN10300: Don't try and #include <linux/slab.h> in lib/inflate.c from bootloader	2010-08-12 09:51:35 -07:00
int_sqrt.c
interval_tree.c
interval_tree_test.c
iomap.c
iomap_copy.c
iommu-common.c
iommu-helper.c
ioremap.c
iov_iter.c
irq_poll.c
irq_regs.c
is_single_threaded.c	lib/is_single_threaded.c: change current_is_single_threaded() to use for_each_thread()	2015-11-06 17:50:42 -08:00
jedec_ddr_data.c
kasprintf.c
Kconfig	raxix-tree: introduce CONFIG_RADIX_TREE_MULTIORDER	2016-05-20 17:58:30 -07:00
Kconfig.debug
Kconfig.kasan
Kconfig.kgdb
Kconfig.kmemcheck
Kconfig.ubsan
kfifo.c
klist.c
kobject.c
kobject_uevent.c	lib/kobject_uevent.c: remove redundant include	2015-02-12 18:54:15 -08:00
kstrtox.c	lib: add "on"/"off" support to kstrtobool	2016-03-17 15:09:34 -07:00
kstrtox.h
lcm.c
libcrc32c.c	Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2016-01-22 11:58:43 -08:00
list_debug.c	list: kill list_force_poison()	2016-03-09 15:43:42 -08:00
list_sort.c	lib/list_sort: use late_initcall to hook in self tests	2015-06-16 14:12:35 -04:00
llist.c	lib/llist.c: fix data race in llist_del_first	2015-11-06 17:50:42 -08:00
locking-selftest-hardirq.h	[PATCH] lockdep: locking API self tests	2006-07-03 15:27:03 -07:00
locking-selftest-mutex.h	[PATCH] lockdep: locking API self tests	2006-07-03 15:27:03 -07:00
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	[PATCH] lockdep: locking API self tests	2006-07-03 15:27:03 -07:00
locking-selftest-spin.h
locking-selftest-wlock-hardirq.h
locking-selftest-wlock-softirq.h	[PATCH] lockdep: locking API self tests	2006-07-03 15:27:03 -07:00
locking-selftest-wlock.h
locking-selftest-wsem.h
locking-selftest.c
lockref.c
lru_cache.c	lru_cache: Converted lc_seq_printf_status to return void	2015-11-25 09:22:02 -07:00
Makefile
md5.c
memory-notifier-error-inject.c	memory: memory notifier error injection module	2012-07-30 17:25:22 -07:00
memweight.c
net_utils.c	mac_pton: Use bool not int return	2014-06-25 17:45:43 -07:00
netdev-notifier-error-inject.c	net: Add support for CHANGEUPPER notifier error injection	2015-12-03 11:49:23 -05:00
nlattr.c	libnl: fix help of _64bit functions	2016-04-23 20:13:24 -04:00
nmi_backtrace.c	printk/nmi: generic solution for safe printk in NMI	2016-05-20 17:58:30 -07:00
nodemask.c	include/linux/nodemask.h: create next_node_in() helper	2016-05-19 19:12:14 -07:00
notifier-error-inject.c
notifier-error-inject.h	fault-injection: notifier error injection	2012-07-30 17:25:22 -07:00
of-reconfig-notifier-error-inject.c
oid_registry.c
once.c
parser.c	lib/parser.c: put EXPORT_SYMBOLs in the conventional place	2014-01-23 16:36:55 -08:00
pci_iomap.c	libnvdimm for 4.3:	2015-09-08 14:35:59 -07:00
percpu-refcount.c
percpu_counter.c
percpu_ida.c	mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM	2015-11-06 17:50:42 -08:00
percpu_test.c
plist.c
pm-notifier-error-inject.c	PM: PM notifier error injection module	2012-07-30 17:25:22 -07:00
radix-tree.c
random32.c
ratelimit.c	ratelimit: extend to print suppressed messages on release	2016-08-02 19:35:06 -04:00
rational.c	lib: Change mail address of Oskar Schirmer	2012-05-17 15:18:37 +02:00
rbtree.c	Introduce rb_replace_node_rcu()	2016-07-06 10:51:14 +01:00
rbtree_test.c	rbtree/test: test rbtree_postorder_for_each_entry_safe()	2014-01-23 16:37:03 -08:00
reciprocal_div.c
rhashtable.c	rhashtable: accept GFP flags in rhashtable_walk_init	2016-04-05 10:56:32 +02:00
scatterlist.c
seq_buf.c
sg_pool.c	lib: scatterlist: move SG pool code from SCSI driver to lib/sg_pool.c	2016-04-15 16:53:14 -04:00
sg_split.c
sha1.c	lib: EXPORT_SYMBOL sha_init	2015-03-23 22:12:08 -04:00
show_mem.c
smp_processor_id.c	percpu: add preemption checks to __this_cpu ops	2014-04-07 16:36:14 -07:00
sort.c	lib/sort: Add 64 bit swap function	2015-06-25 17:00:40 -07:00
stackdepot.c
stmp_device.c
string.c
string_helpers.c
strncpy_from_user.c	unsafe_[get|put]_user: change interface to use a error target label	2016-08-08 13:02:01 -07:00
strnlen_user.c
swiotlb.c
syscall.c
test-kstrtox.c
test-string_helpers.c
test_bitmap.c
test_bpf.c
test_firmware.c	test: firmware_class: add asynchronous request trigger	2016-01-07 13:44:22 -07:00
test_hash.c
test_hexdump.c
test_kasan.c
test_module.c
test_printf.c
test_rhashtable.c
test_static_key_base.c
test_static_keys.c
test_user_copy.c
test_uuid.c
textsearch.c	lib/textsearch.c: remove textsearch_put reference from comments	2014-10-14 02:18:14 +02:00
timerqueue.c
ts_bm.c	textsearch: ts_bm: support case insensitive searching in Boyer-Moore algorithm	2008-07-08 02:37:54 -07:00
ts_fsm.c
ts_kmp.c	textsearch: ts_kmp: support case insensitive searching in Knuth-Morris-Pratt algorithm	2008-07-08 02:38:09 -07:00
ubsan.c
ubsan.h
ucs2_string.c
usercopy.c
uuid.c
vsprintf.c