1 files changed, 57 insertions, 26 deletions

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 07d096c4992..16f73541707 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -35,6 +35,7 @@
 #include <asm/uaccess.h>
 #include <asm/param.h>
 #include <asm/page.h>
+#include <asm/exec.h>
 
 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs);
 static int load_elf_library(struct file *);
@@ -81,9 +82,7 @@ static int set_brk(unsigned long start, unsigned long end)
         end = ELF_PAGEALIGN(end);
         if (end > start) {
                 unsigned long addr;
-                down_write(&current->mm->mmap_sem);
-                addr = do_brk(start, end - start);
-                up_write(&current->mm->mmap_sem);
+                addr = vm_brk(start, end - start);
                 if (BAD_ADDR(addr))
                         return addr;
         }
@@ -513,9 +512,7 @@ static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
                 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
 
                 /* Map the last of the bss segment */
-                down_write(&current->mm->mmap_sem);
-                error = do_brk(elf_bss, last_bss - elf_bss);
-                up_write(&current->mm->mmap_sem);
+                error = vm_brk(elf_bss, last_bss - elf_bss);
                 if (BAD_ADDR(error))
                         goto out_close;
         }
@@ -712,7 +709,6 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
                 goto out_free_dentry;
 
         /* OK, This is the point of no return */
-        current->flags &= ~PF_FORKNOEXEC;
         current->mm->def_flags = def_flags;
 
         /* Do this immediately, since STACK_TOP as used in setup_arg_pages
@@ -934,7 +930,6 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
 
         install_exec_creds(bprm);
-        current->flags &= ~PF_FORKNOEXEC;
         retval = create_elf_tables(bprm, &loc->elf_ex,
                           load_addr, interp_load_addr);
         if (retval < 0) {
@@ -963,10 +958,8 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
                    and some applications "depend" upon this behavior.
                    Since we do not have the power to recompile these, we
                    emulate the SVr4 behavior. Sigh. */
-                down_write(&current->mm->mmap_sem);
-                error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
+                error = vm_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
                                 MAP_FIXED | MAP_PRIVATE, 0);
-                up_write(&current->mm->mmap_sem);
         }
 
 #ifdef ELF_PLAT_INIT
@@ -1051,8 +1044,7 @@ static int load_elf_library(struct file *file)
                 eppnt++;
 
         /* Now use mmap to map the library into memory. */
-        down_write(&current->mm->mmap_sem);
-        error = do_mmap(file,
+        error = vm_mmap(file,
                         ELF_PAGESTART(eppnt->p_vaddr),
                         (eppnt->p_filesz +
                          ELF_PAGEOFFSET(eppnt->p_vaddr)),
@@ -1060,7 +1052,6 @@ static int load_elf_library(struct file *file)
                         MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
                         (eppnt->p_offset -
                          ELF_PAGEOFFSET(eppnt->p_vaddr)));
-        up_write(&current->mm->mmap_sem);
         if (error != ELF_PAGESTART(eppnt->p_vaddr))
                 goto out_free_ph;
 
@@ -1073,11 +1064,8 @@ static int load_elf_library(struct file *file)
         len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
                             ELF_MIN_ALIGN - 1);
         bss = eppnt->p_memsz + eppnt->p_vaddr;
-        if (bss > len) {
-                down_write(&current->mm->mmap_sem);
-                do_brk(len, bss - len);
-                up_write(&current->mm->mmap_sem);
-        }
+        if (bss > len)
+                vm_brk(len, bss - len);
         error = 0;
 
 out_free_ph:
@@ -1095,6 +1083,29 @@ out:
  */
 
 /*
+ * The purpose of always_dump_vma() is to make sure that special kernel mappings
+ * that are useful for post-mortem analysis are included in every core dump.
+ * In that way we ensure that the core dump is fully interpretable later
+ * without matching up the same kernel and hardware config to see what PC values
+ * meant. These special mappings include - vDSO, vsyscall, and other
+ * architecture specific mappings
+ */
+static bool always_dump_vma(struct vm_area_struct *vma)
+{
+        /* Any vsyscall mappings? */
+        if (vma == get_gate_vma(vma->vm_mm))
+                return true;
+        /*
+         * arch_vma_name() returns non-NULL for special architecture mappings,
+         * such as vDSO sections.
+         */
+        if (arch_vma_name(vma))
+                return true;
+
+        return false;
+}
+
+/*
  * Decide what to dump of a segment, part, all or none.
  */
 static unsigned long vma_dump_size(struct vm_area_struct *vma,
@@ -1102,10 +1113,13 @@ static unsigned long vma_dump_size(struct vm_area_struct *vma,
 {
 #define FILTER(type)    (mm_flags & (1UL << MMF_DUMP_##type))
 
-        /* The vma can be set up to tell us the answer directly.  */
-        if (vma->vm_flags & VM_ALWAYSDUMP)
+        /* always dump the vdso and vsyscall sections */
+        if (always_dump_vma(vma))
                 goto whole;
 
+        if (vma->vm_flags & VM_NODUMP)
+                return 0;
+
         /* Hugetlb memory check */
         if (vma->vm_flags & VM_HUGETLB) {
                 if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
@@ -1390,6 +1404,22 @@ static void do_thread_regset_writeback(struct task_struct *task,
                 regset->writeback(task, regset, 1);
 }
 
+#ifndef PR_REG_SIZE
+#define PR_REG_SIZE(S) sizeof(S)
+#endif
+
+#ifndef PRSTATUS_SIZE
+#define PRSTATUS_SIZE(S) sizeof(S)
+#endif
+
+#ifndef PR_REG_PTR
+#define PR_REG_PTR(S) (&((S)->pr_reg))
+#endif
+
+#ifndef SET_PR_FPVALID
+#define SET_PR_FPVALID(S, V) ((S)->pr_fpvalid = (V))
+#endif
+
 static int fill_thread_core_info(struct elf_thread_core_info *t,
                                  const struct user_regset_view *view,
                                  long signr, size_t *total)
@@ -1404,11 +1434,11 @@ static int fill_thread_core_info(struct elf_thread_core_info *t,
          */
         fill_prstatus(&t->prstatus, t->task, signr);
         (void) view->regsets[0].get(t->task, &view->regsets[0],
-                                    0, sizeof(t->prstatus.pr_reg),
-                                    &t->prstatus.pr_reg, NULL);
+                                    0, PR_REG_SIZE(t->prstatus.pr_reg),
+                                    PR_REG_PTR(&t->prstatus), NULL);
 
         fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
-                  sizeof(t->prstatus), &t->prstatus);
+                  PRSTATUS_SIZE(t->prstatus), &t->prstatus);
         *total += notesize(&t->notes[0]);
 
         do_thread_regset_writeback(t->task, &view->regsets[0]);
@@ -1438,7 +1468,7 @@ static int fill_thread_core_info(struct elf_thread_core_info *t,
                                                   regset->core_note_type,
                                                   size, data);
                                 else {
-                                        t->prstatus.pr_fpvalid = 1;
+                                        SET_PR_FPVALID(&t->prstatus, 1);
                                         fill_note(&t->notes[i], "CORE",
                                                   NT_PRFPREG, size, data);
                                 }
@@ -2077,7 +2107,8 @@ out:
 
 static int __init init_elf_binfmt(void)
 {
-        return register_binfmt(&elf_format);
+        register_binfmt(&elf_format);
+        return 0;
 }
 
 static void __exit exit_elf_binfmt(void)