[PATCH 1/5] exec: move allow_write_access/fput to exec_binprm()

Oleg Nesterov
2013-08-02T19:33:00Z

When search_binary_handler() succeeds it does allow_write_access()
and fput(), then it clears bprm->file to ensure the caller will not
do the same.

We can simply move this code to exec_binprm() which is called only
once. In fact we could move this to free_bprm() and remove the same
code in do_execve_common's error path.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
fs/exec.c | 9 +++++----
1 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/fs/exec.c b/fs/exec.c
index ad7d624..ef70320 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1400,10 +1400,6 @@ int search_binary_handler(struct linux_binprm *bprm)
bprm->recursion_depth--;
if (retval >= 0) {
put_binfmt(fmt);
- allow_write_access(bprm->file);
- if (bprm->file)
- fput(bprm->file);
- bprm->file = NULL;
return retval;
}
read_lock(&binfmt_lock);
@@ -1455,6 +1451,11 @@ static int exec_binprm(struct linux_binprm *bprm)
ptrace_event(PTRACE_EVENT_EXEC, old_vpid);
current->did_exec = 1;
proc_exec_connector(current);
+
+ if (bprm->file) {
+ allow_write_access(bprm->file);
+ fput(bprm->file);
+ }
}

return ret;
--
1.5.5.1