path: root/lib
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authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-01 14:41:04 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-01 14:41:04 -0700
commit5db6db0d400edd8bec274e34960cfa22838e1df5 (patch)
tree3d7934f2eb27a2b72b87eae3c2918cf2e635d814 /lib
parent5fab10041b4389b61de7e7a49893190bae686241 (diff)
parent2fefc97b2180518bac923fba3f79fdca1f41dc15 (diff)
Merge branch 'work.uaccess' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull uaccess unification updates from Al Viro: "This is the uaccess unification pile. It's _not_ the end of uaccess work, but the next batch of that will go into the next cycle. This one mostly takes copy_from_user() and friends out of arch/* and gets the zero-padding behaviour in sync for all architectures. Dealing with the nocache/writethrough mess is for the next cycle; fortunately, that's x86-only. Same for cleanups in iov_iter.c (I am sold on access_ok() in there, BTW; just not in this pile), same for reducing __copy_... callsites, strn*... stuff, etc. - there will be a pile about as large as this one in the next merge window. This one sat in -next for weeks. -3KLoC" * 'work.uaccess' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (96 commits) HAVE_ARCH_HARDENED_USERCOPY is unconditional now CONFIG_ARCH_HAS_RAW_COPY_USER is unconditional now m32r: switch to RAW_COPY_USER hexagon: switch to RAW_COPY_USER microblaze: switch to RAW_COPY_USER get rid of padding, switch to RAW_COPY_USER ia64: get rid of copy_in_user() ia64: sanitize __access_ok() ia64: get rid of 'segment' argument of __do_{get,put}_user() ia64: get rid of 'segment' argument of __{get,put}_user_check() ia64: add extable.h powerpc: get rid of zeroing, switch to RAW_COPY_USER esas2r: don't open-code memdup_user() alpha: fix stack smashing in old_adjtimex(2) don't open-code kernel_setsockopt() mips: switch to RAW_COPY_USER mips: get rid of tail-zeroing in primitives mips: make copy_from_user() zero tail explicitly mips: clean and reorder the forest of macros... mips: consolidate __invoke_... wrappers ...
Diffstat (limited to 'lib')
3 files changed, 30 insertions, 4 deletions
diff --git a/lib/Makefile b/lib/Makefile
index 320ac46a8725..b47cf97e1e68 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -41,7 +41,7 @@ obj-y += bcd.o div64.o sort.o parser.o debug_locks.o random32.o \
gcd.o lcm.o list_sort.o uuid.o flex_array.o iov_iter.o clz_ctz.o \
bsearch.o find_bit.o llist.o memweight.o kfifo.o \
percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o \
- once.o refcount.o
+ once.o refcount.o usercopy.o
obj-y += string_helpers.o
obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o
obj-y += hexdump.o
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index cc001a542cb5..4952311422c1 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -413,7 +413,7 @@ void iov_iter_init(struct iov_iter *i, int direction,
size_t count)
/* It will get better. Eventually... */
- if (segment_eq(get_fs(), KERNEL_DS)) {
+ if (uaccess_kernel()) {
direction |= ITER_KVEC;
i->type = direction;
i->kvec = (struct kvec *)iov;
@@ -604,7 +604,7 @@ size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i)
return 0;
iterate_and_advance(i, bytes, v,
- __copy_from_user_nocache((to += v.iov_len) - v.iov_len,
+ __copy_from_user_inatomic_nocache((to += v.iov_len) - v.iov_len,
v.iov_base, v.iov_len),
memcpy_from_page((to += v.bv_len) - v.bv_len, v.bv_page,
v.bv_offset, v.bv_len),
@@ -625,7 +625,7 @@ bool copy_from_iter_full_nocache(void *addr, size_t bytes, struct iov_iter *i)
if (unlikely(i->count < bytes))
return false;
iterate_all_kinds(i, bytes, v, ({
- if (__copy_from_user_nocache((to += v.iov_len) - v.iov_len,
+ if (__copy_from_user_inatomic_nocache((to += v.iov_len) - v.iov_len,
v.iov_base, v.iov_len))
return false;
diff --git a/lib/usercopy.c b/lib/usercopy.c
new file mode 100644
index 000000000000..1b6010a3beb8
--- /dev/null
+++ b/lib/usercopy.c
@@ -0,0 +1,26 @@
+#include <linux/uaccess.h>
+/* out-of-line parts */
+unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n)
+ unsigned long res = n;
+ if (likely(access_ok(VERIFY_READ, from, n)))
+ res = raw_copy_from_user(to, from, n);
+ if (unlikely(res))
+ memset(to + (n - res), 0, res);
+ return res;
+unsigned long _copy_to_user(void *to, const void __user *from, unsigned long n)
+ if (likely(access_ok(VERIFY_WRITE, to, n)))
+ n = raw_copy_to_user(to, from, n);
+ return n;

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