ext4: check EA value offset when loading

[firefly-linux-kernel-4.4.55.git] / fs / binfmt_elf.c

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 86af964c2425d7077467bf54eaecde3d2d4c4911..3aac8e9edac32e41795484d890f81e114ca3e26e 100644 (file)
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -240,6 +240,9 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
        NEW_AUX_ENT(AT_EGID, from_kgid_munged(cred->user_ns, cred->egid));
        NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
        NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
+#ifdef ELF_HWCAP2
+       NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2);
+#endif
        NEW_AUX_ENT(AT_EXECFN, bprm->exec);
        if (k_platform) {
                NEW_AUX_ENT(AT_PLATFORM,
@@ -803,7 +806,8 @@ static int load_elf_binary(struct linux_binprm *bprm)
                         * follow the loader, and is not movable.  */
 #ifdef CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE
                        /* Memory randomization might have been switched off
-                        * in runtime via sysctl.
+                        * in runtime via sysctl or explicit setting of
+                        * personality flags.
                         * If that is the case, retain the original non-zero
                         * load_bias value in order to establish proper
                         * non-randomized mappings.
@@ -1411,7 +1415,7 @@ static void fill_siginfo_note(struct memelfnote *note, user_siginfo_t *csigdata,
  *   long file_ofs
  * followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL...
  */
-static void fill_files_note(struct memelfnote *note)
+static int fill_files_note(struct memelfnote *note)
 {
        struct vm_area_struct *vma;
        unsigned count, size, names_ofs, remaining, n;
@@ -1426,11 +1430,11 @@ static void fill_files_note(struct memelfnote *note)
        names_ofs = (2 + 3 * count) * sizeof(data[0]);
  alloc:
        if (size >= MAX_FILE_NOTE_SIZE) /* paranoia check */
-               goto err;
+               return -EINVAL;
        size = round_up(size, PAGE_SIZE);
        data = vmalloc(size);
        if (!data)
-               goto err;
+               return -ENOMEM;
 
        start_end_ofs = data + 2;
        name_base = name_curpos = ((char *)data) + names_ofs;
@@ -1483,7 +1487,7 @@ static void fill_files_note(struct memelfnote *note)
 
        size = name_curpos - (char *)data;
        fill_note(note, "CORE", NT_FILE, size, data);
- err: ;
+       return 0;
 }
 
 #ifdef CORE_DUMP_USE_REGSET
@@ -1684,8 +1688,8 @@ static int fill_note_info(struct elfhdr *elf, int phdrs,
        fill_auxv_note(&info->auxv, current->mm);
        info->size += notesize(&info->auxv);
 
-       fill_files_note(&info->files);
-       info->size += notesize(&info->files);
+       if (fill_files_note(&info->files) == 0)
+               info->size += notesize(&info->files);
 
        return 1;
 }
@@ -1717,7 +1721,8 @@ static int write_note_info(struct elf_note_info *info,
                        return 0;
                if (first && !writenote(&info->auxv, file, foffset))
                        return 0;
-               if (first && !writenote(&info->files, file, foffset))
+               if (first && info->files.data &&
+                               !writenote(&info->files, file, foffset))
                        return 0;
 
                for (i = 1; i < info->thread_notes; ++i)
@@ -1804,6 +1809,7 @@ static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
 
 struct elf_note_info {
        struct memelfnote *notes;
+       struct memelfnote *notes_files;
        struct elf_prstatus *prstatus;  /* NT_PRSTATUS */
        struct elf_prpsinfo *psinfo;    /* NT_PRPSINFO */
        struct list_head thread_list;
@@ -1894,9 +1900,12 @@ static int fill_note_info(struct elfhdr *elf, int phdrs,
 
        fill_siginfo_note(info->notes + 2, &info->csigdata, siginfo);
        fill_auxv_note(info->notes + 3, current->mm);
-       fill_files_note(info->notes + 4);
+       info->numnote = 4;
 
-       info->numnote = 5;
+       if (fill_files_note(info->notes + info->numnote) == 0) {
+               info->notes_files = info->notes + info->numnote;
+               info->numnote++;
+       }
 
        /* Try to dump the FPU. */
        info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
@@ -1958,8 +1967,9 @@ static void free_note_info(struct elf_note_info *info)
                kfree(list_entry(tmp, struct elf_thread_status, list));
        }
 
-       /* Free data allocated by fill_files_note(): */
-       vfree(info->notes[4].data);
+       /* Free data possibly allocated by fill_files_note(): */
+       if (info->notes_files)
+               vfree(info->notes_files->data);
 
        kfree(info->prstatus);
        kfree(info->psinfo);
@@ -2042,7 +2052,7 @@ static int elf_core_dump(struct coredump_params *cprm)
        struct vm_area_struct *vma, *gate_vma;
        struct elfhdr *elf = NULL;
        loff_t offset = 0, dataoff, foffset;
-       struct elf_note_info info;
+       struct elf_note_info info = { };
        struct elf_phdr *phdr4note = NULL;
        struct elf_shdr *shdr4extnum = NULL;
        Elf_Half e_phnum;
@@ -2091,8 +2101,7 @@ static int elf_core_dump(struct coredump_params *cprm)
                goto cleanup;
 
        has_dumped = 1;
-       current->flags |= PF_DUMPCORE;
-  
+
        fs = get_fs();
        set_fs(KERNEL_DS);