diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2020-12-02 14:15:50 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-12-02 20:49:10 +0100 |
| commit | 923e1e7d8223cfa6e67d00ad238ee415c3c59320 (patch) | |
| tree | e57d071ea98fb3656e671ec6ca05c89dc0c4cb33 /arch/arm64/include/asm/futex.h | |
| parent | arm64: sdei: explicitly simulate PAN/UAO entry (diff) | |
| download | linux-923e1e7d8223cfa6e67d00ad238ee415c3c59320.tar.xz linux-923e1e7d8223cfa6e67d00ad238ee415c3c59320.zip | |
arm64: uaccess: rename privileged uaccess routines
We currently have many uaccess_*{enable,disable}*() variants, which
subsequent patches will cut down as part of removing set_fs() and
friends. Once this simplification is made, most uaccess routines will
only need to ensure that the user page tables are mapped in TTBR0, as is
currently dealt with by uaccess_ttbr0_{enable,disable}().
The existing uaccess_{enable,disable}() routines ensure that user page
tables are mapped in TTBR0, and also disable PAN protections, which is
necessary to be able to use atomics on user memory, but also permit
unrelated privileged accesses to access user memory.
As preparatory step, let's rename uaccess_{enable,disable}() to
uaccess_{enable,disable}_privileged(), highlighting this caveat and
discouraging wider misuse. Subsequent patches can reuse the
uaccess_{enable,disable}() naming for the common case of ensuring the
user page tables are mapped in TTBR0.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201202131558.39270-5-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/include/asm/futex.h')
| -rw-r--r-- | arch/arm64/include/asm/futex.h | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/arm64/include/asm/futex.h b/arch/arm64/include/asm/futex.h index 97f6a63810ec..8e41faa37c69 100644 --- a/arch/arm64/include/asm/futex.h +++ b/arch/arm64/include/asm/futex.h @@ -16,7 +16,7 @@ do { \ unsigned int loops = FUTEX_MAX_LOOPS; \ \ - uaccess_enable(); \ + uaccess_enable_privileged(); \ asm volatile( \ " prfm pstl1strm, %2\n" \ "1: ldxr %w1, %2\n" \ @@ -39,7 +39,7 @@ do { \ "+r" (loops) \ : "r" (oparg), "Ir" (-EFAULT), "Ir" (-EAGAIN) \ : "memory"); \ - uaccess_disable(); \ + uaccess_disable_privileged(); \ } while (0) static inline int @@ -95,7 +95,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *_uaddr, return -EFAULT; uaddr = __uaccess_mask_ptr(_uaddr); - uaccess_enable(); + uaccess_enable_privileged(); asm volatile("// futex_atomic_cmpxchg_inatomic\n" " prfm pstl1strm, %2\n" "1: ldxr %w1, %2\n" @@ -118,7 +118,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *_uaddr, : "+r" (ret), "=&r" (val), "+Q" (*uaddr), "=&r" (tmp), "+r" (loops) : "r" (oldval), "r" (newval), "Ir" (-EFAULT), "Ir" (-EAGAIN) : "memory"); - uaccess_disable(); + uaccess_disable_privileged(); if (!ret) *uval = val; |