From 0557d64d983e3dedead2d4b4e8abc49620d5f5d2 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 18 Feb 2020 12:14:34 -0500 Subject: x86: switch to ->regset_get() All instances of ->get() in arch/x86 switched; that might or might not be worth splitting up. Notes: * for xstateregs_get() the amount we want to store is determined at the boot time; see init_xstate_size() and update_regset_xstate_info() for details. task->thread.fpu.state.xsave ends with a flexible array member and the amount of data in it depends upon the FPU features supported/enabled. * fpregs_get() writes slightly less than full ->thread.fpu.state.fsave (the last word is not copied); we pass the full size of state.fsave and let membuf_write() trim to the amount declared by regset - __regset_get() will make sure that the space in buffer is no more than that. * copy_xstate_to_user() and its helpers are gone now. * fpregs_soft_get() was getting user_regset_copyout() arguments wrong. Since "x86: x86 user_regset math_emu" back in 2008... I really doubt that it's worth splitting out for -stable, though - you need a 486SX box for that to trigger... [Kevin's braino fix for copy_xstate_to_kernel() essentially duplicated here] Signed-off-by: Al Viro --- arch/x86/kernel/ptrace.c | 75 +++++++++++++++--------------------------------- 1 file changed, 23 insertions(+), 52 deletions(-) (limited to 'arch/x86/kernel/ptrace.c') diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c index 44130588987f..8413cb1285a7 100644 --- a/arch/x86/kernel/ptrace.c +++ b/arch/x86/kernel/ptrace.c @@ -433,26 +433,12 @@ static unsigned long getreg(struct task_struct *task, unsigned long offset) static int genregs_get(struct task_struct *target, const struct user_regset *regset, - unsigned int pos, unsigned int count, - void *kbuf, void __user *ubuf) + struct membuf to) { - if (kbuf) { - unsigned long *k = kbuf; - while (count >= sizeof(*k)) { - *k++ = getreg(target, pos); - count -= sizeof(*k); - pos += sizeof(*k); - } - } else { - unsigned long __user *u = ubuf; - while (count >= sizeof(*u)) { - if (__put_user(getreg(target, pos), u++)) - return -EFAULT; - count -= sizeof(*u); - pos += sizeof(*u); - } - } + int reg; + for (reg = 0; to.left; reg++) + membuf_store(&to, getreg(target, reg * sizeof(unsigned long))); return 0; } @@ -716,16 +702,14 @@ static int ioperm_active(struct task_struct *target, static int ioperm_get(struct task_struct *target, const struct user_regset *regset, - unsigned int pos, unsigned int count, - void *kbuf, void __user *ubuf) + struct membuf to) { struct io_bitmap *iobm = target->thread.io_bitmap; if (!iobm) return -ENXIO; - return user_regset_copyout(&pos, &count, &kbuf, &ubuf, - iobm->bitmap, 0, IO_BITMAP_BYTES); + return membuf_write(&to, iobm->bitmap, IO_BITMAP_BYTES); } /* @@ -1003,28 +987,15 @@ static int getreg32(struct task_struct *child, unsigned regno, u32 *val) static int genregs32_get(struct task_struct *target, const struct user_regset *regset, - unsigned int pos, unsigned int count, - void *kbuf, void __user *ubuf) + struct membuf to) { - if (kbuf) { - compat_ulong_t *k = kbuf; - while (count >= sizeof(*k)) { - getreg32(target, pos, k++); - count -= sizeof(*k); - pos += sizeof(*k); - } - } else { - compat_ulong_t __user *u = ubuf; - while (count >= sizeof(*u)) { - compat_ulong_t word; - getreg32(target, pos, &word); - if (__put_user(word, u++)) - return -EFAULT; - count -= sizeof(*u); - pos += sizeof(*u); - } - } + int reg; + for (reg = 0; to.left; reg++) { + u32 val; + getreg32(target, reg * 4, &val); + membuf_store(&to, val); + } return 0; } @@ -1234,25 +1205,25 @@ static struct user_regset x86_64_regsets[] __ro_after_init = { .core_note_type = NT_PRSTATUS, .n = sizeof(struct user_regs_struct) / sizeof(long), .size = sizeof(long), .align = sizeof(long), - .get = genregs_get, .set = genregs_set + .regset_get = genregs_get, .set = genregs_set }, [REGSET_FP] = { .core_note_type = NT_PRFPREG, .n = sizeof(struct user_i387_struct) / sizeof(long), .size = sizeof(long), .align = sizeof(long), - .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set + .active = regset_xregset_fpregs_active, .regset_get = xfpregs_get, .set = xfpregs_set }, [REGSET_XSTATE] = { .core_note_type = NT_X86_XSTATE, .size = sizeof(u64), .align = sizeof(u64), - .active = xstateregs_active, .get = xstateregs_get, + .active = xstateregs_active, .regset_get = xstateregs_get, .set = xstateregs_set }, [REGSET_IOPERM64] = { .core_note_type = NT_386_IOPERM, .n = IO_BITMAP_LONGS, .size = sizeof(long), .align = sizeof(long), - .active = ioperm_active, .get = ioperm_get + .active = ioperm_active, .regset_get = ioperm_get }, }; @@ -1275,24 +1246,24 @@ static struct user_regset x86_32_regsets[] __ro_after_init = { .core_note_type = NT_PRSTATUS, .n = sizeof(struct user_regs_struct32) / sizeof(u32), .size = sizeof(u32), .align = sizeof(u32), - .get = genregs32_get, .set = genregs32_set + .regset_get = genregs32_get, .set = genregs32_set }, [REGSET_FP] = { .core_note_type = NT_PRFPREG, .n = sizeof(struct user_i387_ia32_struct) / sizeof(u32), .size = sizeof(u32), .align = sizeof(u32), - .active = regset_fpregs_active, .get = fpregs_get, .set = fpregs_set + .active = regset_fpregs_active, .regset_get = fpregs_get, .set = fpregs_set }, [REGSET_XFP] = { .core_note_type = NT_PRXFPREG, .n = sizeof(struct user32_fxsr_struct) / sizeof(u32), .size = sizeof(u32), .align = sizeof(u32), - .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set + .active = regset_xregset_fpregs_active, .regset_get = xfpregs_get, .set = xfpregs_set }, [REGSET_XSTATE] = { .core_note_type = NT_X86_XSTATE, .size = sizeof(u64), .align = sizeof(u64), - .active = xstateregs_active, .get = xstateregs_get, + .active = xstateregs_active, .regset_get = xstateregs_get, .set = xstateregs_set }, [REGSET_TLS] = { @@ -1301,13 +1272,13 @@ static struct user_regset x86_32_regsets[] __ro_after_init = { .size = sizeof(struct user_desc), .align = sizeof(struct user_desc), .active = regset_tls_active, - .get = regset_tls_get, .set = regset_tls_set + .regset_get = regset_tls_get, .set = regset_tls_set }, [REGSET_IOPERM32] = { .core_note_type = NT_386_IOPERM, .n = IO_BITMAP_BYTES / sizeof(u32), .size = sizeof(u32), .align = sizeof(u32), - .active = ioperm_active, .get = ioperm_get + .active = ioperm_active, .regset_get = ioperm_get }, }; -- cgit