diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2013-09-12 01:24:42 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-09-12 02:59:05 +0400 |
| commit | 92eaa565add62d56b90987f58ea9feafc5a7c183 (patch) | |
| tree | 78f7bfaa0b99b2b2f5b554bc883b67ac68412e21 /fs | |
| parent | 52f14282bb0c3d3e5ba2a9eaacb12ff37a033e7e (diff) | |
| download | linux-92eaa565add62d56b90987f58ea9feafc5a7c183.tar.xz | |
exec: kill ->load_binary != NULL check in search_binary_handler()
search_binary_handler() checks ->load_binary != NULL for no reason, this
method should be always defined. Turn this check into WARN_ON() and move
it into __register_binfmt().
Also, kill the function pointer. The current code looks confusing, as if
->load_binary can go away after read_unlock(&binfmt_lock). But we rely on
module_get(fmt->module), this fmt can't be changed or unregistered,
otherwise this code is buggy anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Zach Levis <zml@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/exec.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/fs/exec.c b/fs/exec.c index a4cfd1d725e0..7b92fbfa63aa 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -74,6 +74,8 @@ static DEFINE_RWLOCK(binfmt_lock); void __register_binfmt(struct linux_binfmt * fmt, int insert) { BUG_ON(!fmt); + if (WARN_ON(!fmt->load_binary)) + return; write_lock(&binfmt_lock); insert ? list_add(&fmt->lh, &formats) : list_add_tail(&fmt->lh, &formats); @@ -1389,14 +1391,11 @@ int search_binary_handler(struct linux_binprm *bprm) for (try=0; try<2; try++) { read_lock(&binfmt_lock); list_for_each_entry(fmt, &formats, lh) { - int (*fn)(struct linux_binprm *) = fmt->load_binary; - if (!fn) - continue; if (!try_module_get(fmt->module)) continue; read_unlock(&binfmt_lock); bprm->recursion_depth++; - retval = fn(bprm); + retval = fmt->load_binary(bprm); bprm->recursion_depth--; if (retval >= 0) { put_binfmt(fmt); |