diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2017-04-10 17:14:28 +0200 |
|---|---|---|
| committer | Mister Oyster <oysterized@gmail.com> | 2017-07-04 12:11:19 +0200 |
| commit | 6a958f1a400371ecdd5657b10d1f55658dbc978f (patch) | |
| tree | 55035c8ad5b7ff25136964e1c7fc564d9638ea81 /kernel | |
| parent | 0079fdc94ac557d7d1c7fe18945fcc6faa915e4b (diff) | |
x86/vdso: Plug race between mapping and ELF header setup
commit 6fdc6dd90272ce7e75d744f71535cfbd8d77da81 upstream.
The vsyscall32 sysctl can racy against a concurrent fork when it switches
from disabled to enabled:
arch_setup_additional_pages()
if (vdso32_enabled)
--> No mapping
sysctl.vsysscall32()
--> vdso32_enabled = true
create_elf_tables()
ARCH_DLINFO_IA32
if (vdso32_enabled) {
--> Add VDSO entry with NULL pointer
Make ARCH_DLINFO_IA32 check whether the VDSO mapping has been set up for
the newly forked process or not.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathias Krause <minipli@googlemail.com>
Link: http://lkml.kernel.org/r/20170410151723.602367196@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Diffstat (limited to 'kernel')
0 files changed, 0 insertions, 0 deletions