fdpic: check that the size returned by kernel_read() is what we asked for

Check that the size of the read returned by kernel_read() is what we asked
for.  If it isn't, then reject the binary as being a badly formatted.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Howells 2008-04-29 00:59:34 -07:00 committed by Linus Torvalds
parent 76308da189
commit e1d2c8b69a

View file

@ -136,8 +136,8 @@ static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params,
retval = kernel_read(file, params->hdr.e_phoff,
(char *) params->phdrs, size);
if (retval < 0)
return retval;
if (unlikely(retval != size))
return retval < 0 ? retval : -ENOEXEC;
/* determine stack size for this binary */
phdr = params->phdrs;
@ -218,8 +218,11 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm,
phdr->p_offset,
interpreter_name,
phdr->p_filesz);
if (retval < 0)
if (unlikely(retval != phdr->p_filesz)) {
if (retval >= 0)
retval = -ENOEXEC;
goto error;
}
retval = -ENOENT;
if (interpreter_name[phdr->p_filesz - 1] != '\0')
@ -245,8 +248,11 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm,
retval = kernel_read(interpreter, 0, bprm->buf,
BINPRM_BUF_SIZE);
if (retval < 0)
if (unlikely(retval != BINPRM_BUF_SIZE)) {
if (retval >= 0)
retval = -ENOEXEC;
goto error;
}
interp_params.hdr = *((struct elfhdr *) bprm->buf);
break;