Implement ->proc_ioctl_buf() so procfs copies the arguments in before it pins the entry and back out after unpinning it. The native and the 32-bit commands encode their arguments and share one table. mtrr_ioctl() reads and fills procfs' copy, also in the 32-bit layouts.
Signed-off-by: Christian Brauner (Amutable) <[email protected]> --- arch/x86/kernel/cpu/mtrr/if.c | 79 +++++++++++++++++++++++++------------------ 1 file changed, 46 insertions(+), 33 deletions(-) diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c index 038e2dc38797..9c33c0428dfe 100644 --- a/arch/x86/kernel/cpu/mtrr/if.c +++ b/arch/x86/kernel/cpu/mtrr/if.c @@ -149,7 +149,7 @@ mtrr_write(struct file *file, char *buf, size_t len, loff_t * ppos) } static long -mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) +mtrr_ioctl(struct file *file, unsigned int cmd, void *arg) { int err = 0; mtrr_type type; @@ -157,7 +157,6 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) unsigned long size; struct mtrr_sentry sentry; struct mtrr_gentry gentry; - void __user *arg = (void __user *) __arg; memset(&gentry, 0, sizeof(gentry)); @@ -170,13 +169,11 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) case MTRRIOC_SET_PAGE_ENTRY: case MTRRIOC_DEL_PAGE_ENTRY: case MTRRIOC_KILL_PAGE_ENTRY: - if (copy_from_user(&sentry, arg, sizeof(sentry))) - return -EFAULT; + memcpy(&sentry, arg, sizeof(sentry)); break; case MTRRIOC_GET_ENTRY: case MTRRIOC_GET_PAGE_ENTRY: - if (copy_from_user(&gentry, arg, sizeof(gentry))) - return -EFAULT; + memcpy(&gentry, arg, sizeof(gentry)); break; #ifdef CONFIG_COMPAT case MTRRIOC32_ADD_ENTRY: @@ -187,27 +184,21 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) case MTRRIOC32_SET_PAGE_ENTRY: case MTRRIOC32_DEL_PAGE_ENTRY: case MTRRIOC32_KILL_PAGE_ENTRY: { - struct mtrr_sentry32 __user *s32; + struct mtrr_sentry32 *s32 = arg; - s32 = (struct mtrr_sentry32 __user *)__arg; - err = get_user(sentry.base, &s32->base); - err |= get_user(sentry.size, &s32->size); - err |= get_user(sentry.type, &s32->type); - if (err) - return err; + sentry.base = s32->base; + sentry.size = s32->size; + sentry.type = s32->type; break; } case MTRRIOC32_GET_ENTRY: case MTRRIOC32_GET_PAGE_ENTRY: { - struct mtrr_gentry32 __user *g32; + struct mtrr_gentry32 *g32 = arg; - g32 = (struct mtrr_gentry32 __user *)__arg; - err = get_user(gentry.regnum, &g32->regnum); - err |= get_user(gentry.base, &g32->base); - err |= get_user(gentry.size, &g32->size); - err |= get_user(gentry.type, &g32->type); - if (err) - return err; + gentry.regnum = g32->regnum; + gentry.base = g32->base; + gentry.size = g32->size; + gentry.type = g32->type; break; } #endif @@ -312,19 +303,17 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) switch (cmd) { case MTRRIOC_GET_ENTRY: case MTRRIOC_GET_PAGE_ENTRY: - if (copy_to_user(arg, &gentry, sizeof(gentry))) - err = -EFAULT; + memcpy(arg, &gentry, sizeof(gentry)); break; #ifdef CONFIG_COMPAT case MTRRIOC32_GET_ENTRY: case MTRRIOC32_GET_PAGE_ENTRY: { - struct mtrr_gentry32 __user *g32; + struct mtrr_gentry32 *g32 = arg; - g32 = (struct mtrr_gentry32 __user *)__arg; - err = put_user(gentry.base, &g32->base); - err |= put_user(gentry.size, &g32->size); - err |= put_user(gentry.regnum, &g32->regnum); - err |= put_user(gentry.type, &g32->type); + g32->base = gentry.base; + g32->size = gentry.size; + g32->regnum = gentry.regnum; + g32->type = gentry.type; break; } #endif @@ -393,14 +382,38 @@ static int mtrr_open(struct inode *inode, struct file *file) return 0; } +static const struct proc_ioctl_arg mtrr_ioctl_args[] = { + PROC_IOCTL_IOC(MTRRIOC_ADD_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_SET_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_DEL_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_GET_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_KILL_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_ADD_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_SET_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_DEL_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_GET_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_KILL_PAGE_ENTRY), +#ifdef CONFIG_COMPAT + PROC_IOCTL_IOC(MTRRIOC32_ADD_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_SET_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_DEL_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_GET_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_KILL_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_ADD_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_SET_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_DEL_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_GET_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_KILL_PAGE_ENTRY), +#endif +}; + static const struct proc_ops mtrr_proc_ops = { .proc_show = mtrr_seq_show, .proc_open = mtrr_open, .proc_write_buf = mtrr_write, - .proc_ioctl = mtrr_ioctl, -#ifdef CONFIG_COMPAT - .proc_compat_ioctl = mtrr_ioctl, -#endif + .proc_ioctl_buf = mtrr_ioctl, + .proc_ioctl_args = mtrr_ioctl_args, + .proc_nr_ioctl_args = ARRAY_SIZE(mtrr_ioctl_args), .proc_release = mtrr_close, }; -- 2.53.0
