Merge branch 'fix-max-write' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm

Pull dlm fix from David Teigland:
 "Thanks to Jana who reported the problem and was able to test this fix
  so quickly."

This fixes an incorrect size check that triggered for CONFIG_COMPAT
whether the code was actually doing compat or not.  The incorrect write
size check broke userland (clvmd) when maximum resource name lengths are
used.

* 'fix-max-write' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  dlm: check the write size from user
This commit is contained in:
Linus Torvalds 2013-02-05 20:50:11 +11:00
commit fe547d7714

View File

@ -503,11 +503,11 @@ static ssize_t device_write(struct file *file, const char __user *buf,
#endif
return -EINVAL;
#ifdef CONFIG_COMPAT
if (count > sizeof(struct dlm_write_request32) + DLM_RESNAME_MAXLEN)
#else
/*
* can't compare against COMPAT/dlm_write_request32 because
* we don't yet know if is64bit is zero
*/
if (count > sizeof(struct dlm_write_request) + DLM_RESNAME_MAXLEN)
#endif
return -EINVAL;
kbuf = kzalloc(count + 1, GFP_NOFS);