bin_elf_fdpic: check the return value of clear_user

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index f3e72c5..70cfc4b 100644 (file)
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -972,9 +972,12 @@ static int elf_fdpic_map_file_constdisp_on_uclinux(
                        params->elfhdr_addr = seg->addr;
 
                /* clear any space allocated but not loaded */
-               if (phdr->p_filesz < phdr->p_memsz)
-                       clear_user((void *) (seg->addr + phdr->p_filesz),
-                                  phdr->p_memsz - phdr->p_filesz);
+               if (phdr->p_filesz < phdr->p_memsz) {
+                       ret = clear_user((void *) (seg->addr + phdr->p_filesz),
+                                        phdr->p_memsz - phdr->p_filesz);
+                       if (ret)
+                               return ret;
+               }
 
                if (mm) {
                        if (phdr->p_flags & PF_X) {
@@ -1014,7 +1017,7 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
        struct elf32_fdpic_loadseg *seg;
        struct elf32_phdr *phdr;
        unsigned long load_addr, delta_vaddr;
-       int loop, dvset;
+       int loop, dvset, ret;
 
        load_addr = params->load_addr;
        delta_vaddr = 0;
@@ -1114,7 +1117,9 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
                 * PT_LOAD */
                if (prot & PROT_WRITE && disp > 0) {
                        kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp);
-                       clear_user((void __user *) maddr, disp);
+                       ret = clear_user((void __user *) maddr, disp);
+                       if (ret)
+                               return ret;
                        maddr += disp;
                }
 
@@ -1149,15 +1154,19 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
                if (prot & PROT_WRITE && excess1 > 0) {
                        kdebug("clear[%d] ad=%lx sz=%lx",
                               loop, maddr + phdr->p_filesz, excess1);
-                       clear_user((void __user *) maddr + phdr->p_filesz,
-                                  excess1);
+                       ret = clear_user((void __user *) maddr + phdr->p_filesz,
+                                        excess1);
+                       if (ret)
+                               return ret;
                }
 
 #else
                if (excess > 0) {
                        kdebug("clear[%d] ad=%lx sz=%lx",
                               loop, maddr + phdr->p_filesz, excess);
-                       clear_user((void *) maddr + phdr->p_filesz, excess);
+                       ret = clear_user((void *) maddr + phdr->p_filesz, excess);
+                       if (ret)
+                               return ret;
                }
 #endif