[PATCH] binfmt: fix uaccess handling

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 7 insertions, 4 deletions

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index b2efbaead6c3..68e20d5bfe1b 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -243,8 +243,9 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
         if (interp_aout) {
                 argv = sp + 2;
                 envp = argv + argc + 1;
-                __put_user((elf_addr_t)(unsigned long)argv, sp++);
-                __put_user((elf_addr_t)(unsigned long)envp, sp++);
+                if (__put_user((elf_addr_t)(unsigned long)argv, sp++) ||
+                    __put_user((elf_addr_t)(unsigned long)envp, sp++))
+                        return -EFAULT;
         } else {
                 argv = sp;
                 envp = argv + argc + 1;
@@ -254,7 +255,8 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
         p = current->mm->arg_end = current->mm->arg_start;
         while (argc-- > 0) {
                 size_t len;
-                __put_user((elf_addr_t)p, argv++);
+                if (__put_user((elf_addr_t)p, argv++))
+                        return -EFAULT;
                 len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
                 if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
                         return 0;
@@ -265,7 +267,8 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
         current->mm->arg_end = current->mm->env_start = p;
         while (envc-- > 0) {
                 size_t len;
-                __put_user((elf_addr_t)p, envp++);
+                if (__put_user((elf_addr_t)p, envp++))
+                        return -EFAULT;
                 len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
                 if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
                         return 0;