Stop providing the possibility to override the address space using set_fs() now that there is no need for that any more. Signed-off-by: Christoph Hellwig <hch@xxxxxx> --- arch/powerpc/Kconfig | 1 - arch/powerpc/include/asm/processor.h | 7 ---- arch/powerpc/include/asm/thread_info.h | 5 +-- arch/powerpc/include/asm/uaccess.h | 57 +++++++------------------- arch/powerpc/kernel/signal.c | 3 -- arch/powerpc/lib/sstep.c | 6 +-- 6 files changed, 18 insertions(+), 61 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 4d1c18a3b83977..65bed1fdeaad71 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -249,7 +249,6 @@ config PPC select PCI_SYSCALL if PCI select PPC_DAWR if PPC64 select RTC_LIB - select SET_FS select SPARSE_IRQ select SYSCTL_EXCEPTION_TRACE select THREAD_INFO_IN_TASK diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index ed0d633ab5aa42..f01e4d650c520a 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -83,10 +83,6 @@ struct task_struct; void start_thread(struct pt_regs *regs, unsigned long fdptr, unsigned long sp); void release_thread(struct task_struct *); -typedef struct { - unsigned long seg; -} mm_segment_t; - #define TS_FPR(i) fp_state.fpr[i][TS_FPROFFSET] #define TS_CKFPR(i) ckfp_state.fpr[i][TS_FPROFFSET] @@ -148,7 +144,6 @@ struct thread_struct { unsigned long ksp_vsid; #endif struct pt_regs *regs; /* Pointer to saved register state */ - mm_segment_t addr_limit; /* for get_fs() validation */ #ifdef CONFIG_BOOKE /* BookE base exception scratch space; align on cacheline */ unsigned long normsave[8] ____cacheline_aligned; @@ -295,7 +290,6 @@ struct thread_struct { #define INIT_THREAD { \ .ksp = INIT_SP, \ .ksp_limit = INIT_SP_LIMIT, \ - .addr_limit = KERNEL_DS, \ .pgdir = swapper_pg_dir, \ .fpexc_mode = MSR_FE0 | MSR_FE1, \ SPEFSCR_INIT \ @@ -303,7 +297,6 @@ struct thread_struct { #else #define INIT_THREAD { \ .ksp = INIT_SP, \ - .addr_limit = KERNEL_DS, \ .fpexc_mode = 0, \ } #endif diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h index ca6c9702570494..46a210b03d2b80 100644 --- a/arch/powerpc/include/asm/thread_info.h +++ b/arch/powerpc/include/asm/thread_info.h @@ -90,7 +90,6 @@ void arch_setup_new_exec(void); #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ #define TIF_SIGPENDING 1 /* signal pending */ #define TIF_NEED_RESCHED 2 /* rescheduling necessary */ -#define TIF_FSCHECK 3 /* Check FS is USER_DS on return */ #define TIF_SYSCALL_EMU 4 /* syscall emulation active */ #define TIF_RESTORE_TM 5 /* need to restore TM FP/VEC/VSX */ #define TIF_PATCH_PENDING 6 /* pending live patching update */ @@ -130,7 +129,6 @@ void arch_setup_new_exec(void); #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT) #define _TIF_EMULATE_STACK_STORE (1<<TIF_EMULATE_STACK_STORE) #define _TIF_NOHZ (1<<TIF_NOHZ) -#define _TIF_FSCHECK (1<<TIF_FSCHECK) #define _TIF_SYSCALL_EMU (1<<TIF_SYSCALL_EMU) #define _TIF_SYSCALL_DOTRACE (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \ @@ -138,8 +136,7 @@ void arch_setup_new_exec(void); #define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \ _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ - _TIF_RESTORE_TM | _TIF_PATCH_PENDING | \ - _TIF_FSCHECK) + _TIF_RESTORE_TM | _TIF_PATCH_PENDING) #define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR) /* Bits in local_flags */ diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h index 7fe3531ad36a77..5363f7fc6dd06c 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -8,62 +8,33 @@ #include <asm/extable.h> #include <asm/kup.h> -/* - * The fs value determines whether argument validity checking should be - * performed or not. If get_fs() == USER_DS, checking is performed, with - * get_fs() == KERNEL_DS, checking is bypassed. - * - * For historical reasons, these macros are grossly misnamed. - * - * The fs/ds values are now the highest legal address in the "segment". - * This simplifies the checking in the routines below. - */ - -#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) - -#define KERNEL_DS MAKE_MM_SEG(~0UL) #ifdef __powerpc64__ /* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */ -#define USER_DS MAKE_MM_SEG(TASK_SIZE_USER64 - 1) -#else -#define USER_DS MAKE_MM_SEG(TASK_SIZE - 1) -#endif - -#define get_fs() (current->thread.addr_limit) - -static inline void set_fs(mm_segment_t fs) -{ - current->thread.addr_limit = fs; - /* On user-mode return check addr_limit (fs) is correct */ - set_thread_flag(TIF_FSCHECK); -} - -#define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg) -#define user_addr_max() (get_fs().seg) +#define TASK_SIZE_MAX TASK_SIZE_USER64 -#ifdef __powerpc64__ /* - * This check is sufficient because there is a large enough - * gap between user addresses and the kernel addresses + * This check is sufficient because there is a large enough gap between user + * addresses and the kernel addresses. */ -#define __access_ok(addr, size, segment) \ - (((addr) <= (segment).seg) && ((size) <= (segment).seg)) +static inline bool __access_ok(unsigned long addr, unsigned long size) +{ + return addr < TASK_SIZE_MAX && size < TASK_SIZE_MAX; +} #else +#define TASK_SIZE_MAX TASK_SIZE -static inline int __access_ok(unsigned long addr, unsigned long size, - mm_segment_t seg) +static inline bool __access_ok(unsigned long addr, unsigned long size) { - if (addr > seg.seg) - return 0; - return (size == 0 || size - 1 <= seg.seg - addr); + if (addr >= TASK_SIZE_MAX) + return false; + return size == 0 || size <= TASK_SIZE_MAX - addr; } - -#endif +#endif /* __powerpc64__ */ #define access_ok(addr, size) \ (__chk_user_ptr(addr), \ - __access_ok((__force unsigned long)(addr), (size), get_fs())) + __access_ok((unsigned long)(addr), (size))) /* * These are the main single-value transfer routines. They automatically diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index d15a98c758b8b4..df547d8e31e49c 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -312,9 +312,6 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags) { user_exit(); - /* Check valid addr_limit, TIF check is done there */ - addr_limit_user_check(); - if (thread_info_flags & _TIF_UPROBE) uprobe_notify_resume(regs); diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index caee8cc77e1954..8342188ea1acd0 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -108,11 +108,11 @@ static nokprobe_inline long address_ok(struct pt_regs *regs, { if (!user_mode(regs)) return 1; - if (__access_ok(ea, nb, USER_DS)) + if (__access_ok(ea, nb)) return 1; - if (__access_ok(ea, 1, USER_DS)) + if (__access_ok(ea, 1)) /* Access overlaps the end of the user region */ - regs->dar = USER_DS.seg; + regs->dar = TASK_SIZE_MAX - 1; else regs->dar = ea; return 0; -- 2.28.0