| Message ID | 1406067727-19683-107-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
On Tue, Jul 22, 2014 at 3:21 PM, Kamal Mostafa <kamal@canonical.com> wrote: > 3.8.13.27 -stable review patch. If anyone has any objections, please let me know. > > ------------------ > > From: Andy Lutomirski <luto@amacapital.net> > > commit 554086d85e71f30abe46fc014fea31929a7c6a8a upstream. > > The bad syscall nr paths are their own incomprehensible route > through the entry control flow. Rearrange them to work just like > syscalls that return -ENOSYS. > > This fixes an OOPS in the audit code when fast-path auditing is > enabled and sysenter gets a bad syscall nr (CVE-2014-4508). > > This has probably been broken since Linux 2.6.27: > af0575bba0 i386 syscall audit fast-path Don't apply this without: https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/commit/?h=x86/urgent&id=8142b215501f8b291a108a202b3a053a265b03dd Sorry! --Andy
On Tue, Jul 22, 2014 at 03:27:59PM -0700, Andy Lutomirski wrote: > On Tue, Jul 22, 2014 at 3:21 PM, Kamal Mostafa <kamal@canonical.com> wrote: > > 3.8.13.27 -stable review patch. If anyone has any objections, please let me know. > > > > ------------------ > > > > From: Andy Lutomirski <luto@amacapital.net> > > > > commit 554086d85e71f30abe46fc014fea31929a7c6a8a upstream. > > > > The bad syscall nr paths are their own incomprehensible route > > through the entry control flow. Rearrange them to work just like > > syscalls that return -ENOSYS. > > > > This fixes an OOPS in the audit code when fast-path auditing is > > enabled and sysenter gets a bad syscall nr (CVE-2014-4508). > > > > This has probably been broken since Linux 2.6.27: > > af0575bba0 i386 syscall audit fast-path > > Don't apply this without: > > https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/commit/?h=x86/urgent&id=8142b215501f8b291a108a202b3a053a265b03dd > > Sorry! As that isn't in Linus's tree yet, don't apply that one either... thanks, greg k-h
On Tue, 2014-07-22 at 15:27 -0700, Andy Lutomirski wrote: > On Tue, Jul 22, 2014 at 3:21 PM, Kamal Mostafa <kamal@canonical.com> wrote: > > 3.8.13.27 -stable review patch. If anyone has any objections, please let me know. > > > > ------------------ > > > > From: Andy Lutomirski <luto@amacapital.net> > > > > commit 554086d85e71f30abe46fc014fea31929a7c6a8a upstream. > > > > The bad syscall nr paths are their own incomprehensible route > > [...] > > Don't apply this without: > > https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/commit/?h=x86/urgent&id=8142b215501f8b291a108a202b3a053a265b03dd > > Sorry! No worries -- I've dropped this from the 3.8-stable queue, pending . . . > As that isn't in Linus's tree yet, don't apply that one either... > thanks, > greg k-h . . . that. Thanks Andy and Greg, -Kamal
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index 60d03c2..b32b466 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -434,9 +434,10 @@ sysenter_past_esp: jnz sysenter_audit sysenter_do_call: cmpl $(NR_syscalls), %eax - jae syscall_badsys + jae sysenter_badsys call *sys_call_table(,%eax,4) movl %eax,PT_EAX(%esp) +sysenter_after_call: LOCKDEP_SYS_EXIT DISABLE_INTERRUPTS(CLBR_ANY) TRACE_IRQS_OFF @@ -686,7 +687,12 @@ END(syscall_fault) syscall_badsys: movl $-ENOSYS,PT_EAX(%esp) - jmp resume_userspace + jmp syscall_exit +END(syscall_badsys) + +sysenter_badsys: + movl $-ENOSYS,PT_EAX(%esp) + jmp sysenter_after_call END(syscall_badsys) CFI_ENDPROC /*