Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:
 "87 patches.

  Subsystems affected by this patch series: mm (pagecache and hugetlb),
  procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
  init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
  sysvfs, kcov, gdb, resource, selftests, and ipc"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits)
  ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
  ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
  selftests/kselftest/runner/run_one(): allow running non-executable files
  virtio-mem: disallow mapping virtio-mem memory via /dev/mem
  kernel/resource: disallow access to exclusive system RAM regions
  kernel/resource: clean up and optimize iomem_is_exclusive()
  scripts/gdb: handle split debug for vmlinux
  kcov: replace local_irq_save() with a local_lock_t
  kcov: avoid enable+disable interrupts if !in_task()
  kcov: allocate per-CPU memory on the relevant node
  Documentation/kcov: define `ip' in the example
  Documentation/kcov: include types.h in the example
  sysv: use BUILD_BUG_ON instead of runtime check
  kernel/fork.c: unshare(): use swap() to make code cleaner
  seq_file: fix passing wrong private data
  seq_file: move seq_escape() to a header
  signal: remove duplicate include in signal.h
  crash_dump: remove duplicate include in crash_dump.h
  crash_dump: fix boolreturn.cocci warning
  hfs/hfsplus: use WARN_ON for sanity check
  ...

1 files changed, 23 insertions, 10 deletions

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index fa582748be41..f8c7f26f1fbb 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -156,7 +156,7 @@ static int padzero(unsigned long elf_bss)
 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
 #define STACK_ROUND(sp, items) \
 	(((unsigned long) (sp - items)) &~ 15UL)
-#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
+#define STACK_ALLOC(sp, len) (sp -= len)
 #endif
 
 #ifndef ELF_BASE_PLATFORM
@@ -1074,20 +1074,26 @@ out_free_interp:
 
 		vaddr = elf_ppnt->p_vaddr;
 		/*
-		 * If we are loading ET_EXEC or we have already performed
-		 * the ET_DYN load_addr calculations, proceed normally.
+		 * The first time through the loop, load_addr_set is false:
+		 * layout will be calculated. Once set, use MAP_FIXED since
+		 * we know we've already safely mapped the entire region with
+		 * MAP_FIXED_NOREPLACE in the once-per-binary logic following.
 		 */
-		if (elf_ex->e_type == ET_EXEC || load_addr_set) {
+		if (load_addr_set) {
 			elf_flags |= MAP_FIXED;
+		} else if (elf_ex->e_type == ET_EXEC) {
+			/*
+			 * This logic is run once for the first LOAD Program
+			 * Header for ET_EXEC binaries. No special handling
+			 * is needed.
+			 */
+			elf_flags |= MAP_FIXED_NOREPLACE;
 		} else if (elf_ex->e_type == ET_DYN) {
 			/*
 			 * This logic is run once for the first LOAD Program
 			 * Header for ET_DYN binaries to calculate the
 			 * randomization (load_bias) for all the LOAD
-			 * Program Headers, and to calculate the entire
-			 * size of the ELF mapping (total_size). (Note that
-			 * load_addr_set is set to true later once the
-			 * initial mapping is performed.)
+			 * Program Headers.
 			 *
 			 * There are effectively two types of ET_DYN
 			 * binaries: programs (i.e. PIE: ET_DYN with INTERP)
@@ -1108,7 +1114,7 @@ out_free_interp:
 			 * Therefore, programs are loaded offset from
 			 * ELF_ET_DYN_BASE and loaders are loaded into the
 			 * independently randomized mmap region (0 load_bias
-			 * without MAP_FIXED).
+			 * without MAP_FIXED nor MAP_FIXED_NOREPLACE).
 			 */
 			if (interpreter) {
 				load_bias = ELF_ET_DYN_BASE;
@@ -1117,7 +1123,7 @@ out_free_interp:
 				alignment = maximum_alignment(elf_phdata, elf_ex->e_phnum);
 				if (alignment)
 					load_bias &= ~(alignment - 1);
-				elf_flags |= MAP_FIXED;
+				elf_flags |= MAP_FIXED_NOREPLACE;
 			} else
 				load_bias = 0;
 
@@ -1129,7 +1135,14 @@ out_free_interp:
 			 * is then page aligned.
 			 */
 			load_bias = ELF_PAGESTART(load_bias - vaddr);
+		}
 
+		/*
+		 * Calculate the entire size of the ELF mapping (total_size).
+		 * (Note that load_addr_set is set to true later once the
+		 * initial mapping is performed.)
+		 */
+		if (!load_addr_set) {
 			total_size = total_mapping_size(elf_phdata,
 							elf_ex->e_phnum);
 			if (!total_size) {