From e1d2c8b69ad81ea103b1e87809eba51931e16874 Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 29 Apr 2008 00:59:34 -0700 Subject: [PATCH] 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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/binfmt_elf_fdpic.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c index 32649f2a16..ddd35d8733 100644 --- a/fs/binfmt_elf_fdpic.c +++ b/fs/binfmt_elf_fdpic.c @@ -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; -- 2.39.5