Merge branch 'akpm' (patches from Andrew)

Merge misc updates from Andrew Morton:

 - kasan updates

 - procfs

 - lib/bitmap updates

 - other lib/ updates

 - checkpatch tweaks

 - rapidio

 - ubsan

 - pipe fixes and cleanups

 - lots of other misc bits

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
  Documentation/sysctl/user.txt: fix typo
  MAINTAINERS: update ARM/QUALCOMM SUPPORT patterns
  MAINTAINERS: update various PALM patterns
  MAINTAINERS: update "ARM/OXNAS platform support" patterns
  MAINTAINERS: update Cortina/Gemini patterns
  MAINTAINERS: remove ARM/CLKDEV SUPPORT file pattern
  MAINTAINERS: remove ANDROID ION pattern
  mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors
  mm: docs: fix parameter names mismatch
  mm: docs: fixup punctuation
  pipe: read buffer limits atomically
  pipe: simplify round_pipe_size()
  pipe: reject F_SETPIPE_SZ with size over UINT_MAX
  pipe: fix off-by-one error when checking buffer limits
  pipe: actually allow root to exceed the pipe buffer limits
  pipe, sysctl: remove pipe_proc_fn()
  pipe, sysctl: drop 'min' parameter from pipe-max-size converter
  kasan: rework Kconfig settings
  crash_dump: is_kdump_kernel can be boolean
  kernel/mutex: mutex_is_locked can be boolean
  ...

1 files changed, 5 insertions, 13 deletions

diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index 4bc85cb8be6a..e8a93bc8285d 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -512,23 +512,15 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos)
 				return -EFAULT;
 		} else {
 			if (kern_addr_valid(start)) {
-				unsigned long n;
-
 				/*
 				 * Using bounce buffer to bypass the
 				 * hardened user copy kernel text checks.
 				 */
-				memcpy(buf, (char *) start, tsz);
-				n = copy_to_user(buffer, buf, tsz);
-				/*
-				 * We cannot distinguish between fault on source
-				 * and fault on destination. When this happens
-				 * we clear too and hope it will trigger the
-				 * EFAULT again.
-				 */
-				if (n) { 
-					if (clear_user(buffer + tsz - n,
-								n))
+				if (probe_kernel_read(buf, (void *) start, tsz)) {
+					if (clear_user(buffer, tsz))
+						return -EFAULT;
+				} else {
+					if (copy_to_user(buffer, buf, tsz))
 						return -EFAULT;
 				}
 			} else {