diff options
| author | Andy Lutomirski <luto@kernel.org> | 2018-08-29 17:47:18 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2018-08-31 17:08:22 +0200 |
| commit | 4012e77a903d114f915fc607d6d2ed54a3d6c9b1 (patch) | |
| tree | aa56d63db999604dd3004855996dca36c293e1cf /arch/x86/mm/mmap.c | |
| parent | x86: Allow generating user-space headers without a compiler (diff) | |
| download | linux-4012e77a903d114f915fc607d6d2ed54a3d6c9b1.tar.xz linux-4012e77a903d114f915fc607d6d2ed54a3d6c9b1.zip | |
x86/nmi: Fix NMI uaccess race against CR3 switching
A NMI can hit in the middle of context switching or in the middle of
switch_mm_irqs_off(). In either case, CR3 might not match current->mm,
which could cause copy_from_user_nmi() and friends to read the wrong
memory.
Fix it by adding a new nmi_uaccess_okay() helper and checking it in
copy_from_user_nmi() and in __copy_from_user_nmi()'s callers.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rik van Riel <riel@surriel.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/dd956eba16646fd0b15c3c0741269dfd84452dac.1535557289.git.luto@kernel.org
Diffstat (limited to 'arch/x86/mm/mmap.c')
0 files changed, 0 insertions, 0 deletions