diff options
| author | Anshuman Khandual | 2021-06-15 15:02:58 +0530 |
|---|---|---|
| committer | Will Deacon | 2021-06-15 19:03:24 +0100 |
| commit | 9163f01130304fab1f74683d7d44632da7bda637 (patch) | |
| tree | e3d561784e3a287c37e4b75e716d39b97c63417e /arch/arm64/kernel | |
| parent | 84c5e23edecd7013ceaed8460deed5c33842cb8d (diff) | |
arm64/mm: Fix ttbr0 values stored in struct thread_info for software-pan
When using CONFIG_ARM64_SW_TTBR0_PAN, a task's thread_info::ttbr0 must be
the TTBR0_EL1 value used to run userspace. With 52-bit PAs, the PA must be
packed into the TTBR using phys_to_ttbr(), but we forget to do this in some
of the SW PAN code. Thus, if the value is installed into TTBR0_EL1 (as may
happen in the uaccess routines), this could result in UNPREDICTABLE
behaviour.
Since hardware with 52-bit PA support almost certainly has HW PAN, which
will be used in preference, this shouldn't be a practical issue, but let's
fix this for consistency.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Fixes: 529c4b05a3cb ("arm64: handle 52-bit addresses in TTBR")
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/1623749578-11231-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/setup.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 61845c0821d9..68b30e8c22db 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -381,7 +381,7 @@ void __init __no_sanitize_address setup_arch(char **cmdline_p) * faults in case uaccess_enable() is inadvertently called by the init * thread. */ - init_task.thread_info.ttbr0 = __pa_symbol(reserved_pg_dir); + init_task.thread_info.ttbr0 = phys_to_ttbr(__pa_symbol(reserved_pg_dir)); #endif if (boot_args[1] || boot_args[2] || boot_args[3]) { |