mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 08:19:28 +00:00
Revert "[PATCH] x86-64: Fix up handling of non canonical user RIPs"
This reverts commit c33d4568ac
.
Andrew Clayton and Hugh Dickins report that it's broken for them and
causes strange page table and slab corruption, and spontaneous reboots.
Let's get it right next time.
Cc: Andrew Clayton <andrew@rootshell.co.uk>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
parent
ceb2ca9cb0
commit
cbf0ec6ee0
1 changed files with 18 additions and 11 deletions
|
@ -178,12 +178,6 @@ rff_trace:
|
|||
* Interrupts are off on entry.
|
||||
* Only called from user space.
|
||||
*
|
||||
* EM64T CPUs have somewhat weird error reporting for non canonical RIPs in SYSRET.
|
||||
* We can't handle any exceptions there because the exception handler would
|
||||
* end up running on the user stack which is unsafe. To avoid problems
|
||||
* any code that might end up with a user touched pt_regs should return
|
||||
* using int_ret_from_syscall.
|
||||
*
|
||||
* XXX if we had a free scratch register we could save the RSP into the stack frame
|
||||
* and report it properly in ps. Unfortunately we haven't.
|
||||
*/
|
||||
|
@ -260,9 +254,7 @@ sysret_signal:
|
|||
xorl %esi,%esi # oldset -> arg2
|
||||
call ptregscall_common
|
||||
1: movl $_TIF_NEED_RESCHED,%edi
|
||||
/* Stack frame might have been changed. The IRET path does
|
||||
some additional checks to handle this */
|
||||
jmp int_with_check
|
||||
jmp sysret_check
|
||||
|
||||
badsys:
|
||||
movq $-ENOSYS,RAX-ARGOFFSET(%rsp)
|
||||
|
@ -288,8 +280,7 @@ tracesys:
|
|||
call syscall_trace_leave
|
||||
RESTORE_TOP_OF_STACK %rbx
|
||||
RESTORE_REST
|
||||
/* Stack frame might have been changed. Use the more careful IRET path */
|
||||
jmp int_ret_from_sys_call
|
||||
jmp ret_from_sys_call
|
||||
CFI_ENDPROC
|
||||
|
||||
/*
|
||||
|
@ -417,9 +408,25 @@ ENTRY(stub_execve)
|
|||
CFI_ADJUST_CFA_OFFSET -8
|
||||
CFI_REGISTER rip, r11
|
||||
SAVE_REST
|
||||
movq %r11, %r15
|
||||
CFI_REGISTER rip, r15
|
||||
FIXUP_TOP_OF_STACK %r11
|
||||
call sys_execve
|
||||
GET_THREAD_INFO(%rcx)
|
||||
bt $TIF_IA32,threadinfo_flags(%rcx)
|
||||
CFI_REMEMBER_STATE
|
||||
jc exec_32bit
|
||||
RESTORE_TOP_OF_STACK %r11
|
||||
movq %r15, %r11
|
||||
CFI_REGISTER rip, r11
|
||||
RESTORE_REST
|
||||
pushq %r11
|
||||
CFI_ADJUST_CFA_OFFSET 8
|
||||
CFI_REL_OFFSET rip, 0
|
||||
ret
|
||||
|
||||
exec_32bit:
|
||||
CFI_RESTORE_STATE
|
||||
movq %rax,RAX(%rsp)
|
||||
RESTORE_REST
|
||||
jmp int_ret_from_sys_call
|
||||
|
|
Loading…
Reference in a new issue