1 files changed, 62 insertions, 23 deletions

diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 80c1f952ef78..0e8367c54624 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -25,6 +25,7 @@
 #include <linux/fcntl.h>
 #include <linux/slab.h>
 #include <linux/pagemap.h>
+#include <linux/security.h>
 #include <linux/highmem.h>
 #include <linux/highuid.h>
 #include <linux/personality.h>
@@ -455,8 +456,19 @@ error_kill:
 }
 
 /*****************************************************************************/
+
+#ifndef ELF_BASE_PLATFORM
 /*
- * present useful information to the program
+ * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
+ * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
+ * will be copied to the user stack in the same manner as AT_PLATFORM.
+ */
+#define ELF_BASE_PLATFORM NULL
+#endif
+
+/*
+ * present useful information to the program by shovelling it onto the new
+ * process's stack
  */
 static int create_elf_fdpic_tables(struct linux_binprm *bprm,
                                    struct mm_struct *mm,
@@ -466,15 +478,19 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm,
         unsigned long sp, csp, nitems;
         elf_caddr_t __user *argv, *envp;
         size_t platform_len = 0, len;
-        char *k_platform;
-        char __user *u_platform, *p;
+        char *k_platform, *k_base_platform;
+        char __user *u_platform, *u_base_platform, *p;
         long hwcap;
         int loop;
         int nr; /* reset for each csp adjustment */
 
-        /* we're going to shovel a whole load of stuff onto the stack */
 #ifdef CONFIG_MMU
-        sp = bprm->p;
+        /* In some cases (e.g. Hyper-Threading), we want to avoid L1 evictions
+         * by the processes running on the same package. One thing we can do is
+         * to shuffle the initial stack for them, so we give the architecture
+         * an opportunity to do so here.
+         */
+        sp = arch_align_stack(bprm->p);
 #else
         sp = mm->start_stack;
 
@@ -483,11 +499,14 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm,
                 return -EFAULT;
 #endif
 
-        /* get hold of platform and hardware capabilities masks for the machine
-         * we are running on.  In some cases (Sparc), this info is impossible
-         * to get, in others (i386) it is merely difficult.
-         */
         hwcap = ELF_HWCAP;
+
+        /*
+         * If this architecture has a platform capability string, copy it
+         * to userspace.  In some cases (Sparc), this info is impossible
+         * for userspace to get any other way, in others (i386) it is
+         * merely difficult.
+         */
         k_platform = ELF_PLATFORM;
         u_platform = NULL;
 
@@ -499,19 +518,20 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm,
                         return -EFAULT;
         }
 
-#if defined(__i386__) && defined(CONFIG_SMP)
-        /* in some cases (e.g. Hyper-Threading), we want to avoid L1 evictions
-         * by the processes running on the same package. One thing we can do is
-         * to shuffle the initial stack for them.
-         *
-         * the conditionals here are unneeded, but kept in to make the code
-         * behaviour the same as pre change unless we have hyperthreaded
-         * processors. This keeps Mr Marcelo Person happier but should be
-         * removed for 2.5
+        /*
+         * If this architecture has a "base" platform capability
+         * string, copy it to userspace.
          */
-        if (smp_num_siblings > 1)
-                sp = sp - ((current->pid % 64) << 7);
-#endif
+        k_base_platform = ELF_BASE_PLATFORM;
+        u_base_platform = NULL;
+
+        if (k_base_platform) {
+                platform_len = strlen(k_base_platform) + 1;
+                sp -= platform_len;
+                u_base_platform = (char __user *) sp;
+                if (__copy_to_user(u_base_platform, k_base_platform, platform_len) != 0)
+                        return -EFAULT;
+        }
 
         sp &= ~7UL;
 
@@ -541,9 +561,13 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm,
         }
 
         /* force 16 byte _final_ alignment here for generality */
-#define DLINFO_ITEMS 13
+#define DLINFO_ITEMS 15
+
+        nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) +
+                (k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH;
 
-        nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH;
+        if (bprm->interp_flags & BINPRM_FLAGS_EXECFD)
+                nitems++;
 
         csp = sp;
         sp -= nitems * 2 * sizeof(unsigned long);
@@ -575,6 +599,19 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm,
                             (elf_addr_t) (unsigned long) u_platform);
         }
 
+        if (k_base_platform) {
+                nr = 0;
+                csp -= 2 * sizeof(unsigned long);
+                NEW_AUX_ENT(AT_BASE_PLATFORM,
+                            (elf_addr_t) (unsigned long) u_base_platform);
+        }
+
+        if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
+                nr = 0;
+                csp -= 2 * sizeof(unsigned long);
+                NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
+        }
+
         nr = 0;
         csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long);
         NEW_AUX_ENT(AT_HWCAP,   hwcap);
@@ -590,6 +627,8 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm,
         NEW_AUX_ENT(AT_EUID,    (elf_addr_t) current->euid);
         NEW_AUX_ENT(AT_GID,     (elf_addr_t) current->gid);
         NEW_AUX_ENT(AT_EGID,    (elf_addr_t) current->egid);
+        NEW_AUX_ENT(AT_SECURE,  security_bprm_secureexec(bprm));
+        NEW_AUX_ENT(AT_EXECFN,  bprm->exec);
 
 #ifdef ARCH_DLINFO
         nr = 0;