From bba84aeccafb57f3f175bbab0658a7facd611d18 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 30 Oct 2020 17:44:21 +0100 Subject: scsi: megaraid_sas: Simplify compat_ioctl handling There have been several attempts to fix serious problems in the compat handling in megasas_mgmt_compat_ioctl_fw(), and it also uses the compat_alloc_user_space() function. Folding the compat handling into the regular ioctl function with in_compat_syscall() simplifies it a lot and avoids some of the remaining problems: - missing handling of unaligned pointers - overflowing the ioc->frame.raw array from invalid input - compat_alloc_user_space() Link: https://lore.kernel.org/r/20201030164450.1253641-3-arnd@kernel.org Reviewed-by: Christoph Hellwig Signed-off-by: Arnd Bergmann Signed-off-by: Martin K. Petersen --- drivers/scsi/megaraid/megaraid_sas.h | 2 - drivers/scsi/megaraid/megaraid_sas_base.c | 118 ++++++++++++------------------ 2 files changed, 46 insertions(+), 74 deletions(-) (limited to 'drivers/scsi/megaraid') diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h index 5e4137f10e0e..0f808d63580e 100644 --- a/drivers/scsi/megaraid/megaraid_sas.h +++ b/drivers/scsi/megaraid/megaraid_sas.h @@ -2605,7 +2605,6 @@ struct megasas_aen { u32 class_locale_word; } __attribute__ ((packed)); -#ifdef CONFIG_COMPAT struct compat_megasas_iocpacket { u16 host_no; u16 __pad1; @@ -2621,7 +2620,6 @@ struct compat_megasas_iocpacket { } __attribute__ ((packed)); #define MEGASAS_IOC_FIRMWARE32 _IOWR('M', 1, struct compat_megasas_iocpacket) -#endif #define MEGASAS_IOC_FIRMWARE _IOWR('M', 1, struct megasas_iocpacket) #define MEGASAS_IOC_GET_AEN _IOW('M', 3, struct megasas_aen) diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c index 5e31bd364a5b..242cefc61ca5 100644 --- a/drivers/scsi/megaraid/megaraid_sas_base.c +++ b/drivers/scsi/megaraid/megaraid_sas_base.c @@ -8319,16 +8319,19 @@ megasas_mgmt_fw_ioctl(struct megasas_instance *instance, * copy out the sense */ if (ioc->sense_len) { + void __user *uptr; /* * sense_ptr points to the location that has the user * sense buffer address */ - sense_ptr = (unsigned long *) ((unsigned long)ioc->frame.raw + - ioc->sense_off); + sense_ptr = (void *)ioc->frame.raw + ioc->sense_off; + if (in_compat_syscall()) + uptr = compat_ptr(get_unaligned((compat_uptr_t *) + sense_ptr)); + else + uptr = get_unaligned((void __user **)sense_ptr); - if (copy_to_user((void __user *)((unsigned long) - get_unaligned((unsigned long *)sense_ptr)), - sense, ioc->sense_len)) { + if (copy_to_user(uptr, sense, ioc->sense_len)) { dev_err(&instance->pdev->dev, "Failed to copy out to user " "sense data\n"); error = -EFAULT; @@ -8371,6 +8374,38 @@ out: return error; } +static struct megasas_iocpacket * +megasas_compat_iocpacket_get_user(void __user *arg) +{ + struct megasas_iocpacket *ioc; + struct compat_megasas_iocpacket __user *cioc = arg; + size_t size; + int err = -EFAULT; + int i; + + ioc = kzalloc(sizeof(*ioc), GFP_KERNEL); + if (!ioc) + return ERR_PTR(-ENOMEM); + size = offsetof(struct megasas_iocpacket, frame) + sizeof(ioc->frame); + if (copy_from_user(ioc, arg, size)) + goto out; + + for (i = 0; i < MAX_IOCTL_SGE; i++) { + compat_uptr_t iov_base; + + if (get_user(iov_base, &cioc->sgl[i].iov_base) || + get_user(ioc->sgl[i].iov_len, &cioc->sgl[i].iov_len)) + goto out; + + ioc->sgl[i].iov_base = compat_ptr(iov_base); + } + + return ioc; +out: + kfree(ioc); + return ERR_PTR(err); +} + static int megasas_mgmt_ioctl_fw(struct file *file, unsigned long arg) { struct megasas_iocpacket __user *user_ioc = @@ -8379,7 +8414,11 @@ static int megasas_mgmt_ioctl_fw(struct file *file, unsigned long arg) struct megasas_instance *instance; int error; - ioc = memdup_user(user_ioc, sizeof(*ioc)); + if (in_compat_syscall()) + ioc = megasas_compat_iocpacket_get_user(user_ioc); + else + ioc = memdup_user(user_ioc, sizeof(struct megasas_iocpacket)); + if (IS_ERR(ioc)) return PTR_ERR(ioc); @@ -8484,78 +8523,13 @@ megasas_mgmt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) } #ifdef CONFIG_COMPAT -static int megasas_mgmt_compat_ioctl_fw(struct file *file, unsigned long arg) -{ - struct compat_megasas_iocpacket __user *cioc = - (struct compat_megasas_iocpacket __user *)arg; - struct megasas_iocpacket __user *ioc = - compat_alloc_user_space(sizeof(struct megasas_iocpacket)); - int i; - int error = 0; - compat_uptr_t ptr; - u32 local_sense_off; - u32 local_sense_len; - u32 user_sense_off; - - if (clear_user(ioc, sizeof(*ioc))) - return -EFAULT; - - if (copy_in_user(&ioc->host_no, &cioc->host_no, sizeof(u16)) || - copy_in_user(&ioc->sgl_off, &cioc->sgl_off, sizeof(u32)) || - copy_in_user(&ioc->sense_off, &cioc->sense_off, sizeof(u32)) || - copy_in_user(&ioc->sense_len, &cioc->sense_len, sizeof(u32)) || - copy_in_user(ioc->frame.raw, cioc->frame.raw, 128) || - copy_in_user(&ioc->sge_count, &cioc->sge_count, sizeof(u32))) - return -EFAULT; - - /* - * The sense_ptr is used in megasas_mgmt_fw_ioctl only when - * sense_len is not null, so prepare the 64bit value under - * the same condition. - */ - if (get_user(local_sense_off, &ioc->sense_off) || - get_user(local_sense_len, &ioc->sense_len) || - get_user(user_sense_off, &cioc->sense_off)) - return -EFAULT; - - if (local_sense_off != user_sense_off) - return -EINVAL; - - if (local_sense_len) { - void __user **sense_ioc_ptr = - (void __user **)((u8 *)((unsigned long)&ioc->frame.raw) + local_sense_off); - compat_uptr_t *sense_cioc_ptr = - (compat_uptr_t *)(((unsigned long)&cioc->frame.raw) + user_sense_off); - if (get_user(ptr, sense_cioc_ptr) || - put_user(compat_ptr(ptr), sense_ioc_ptr)) - return -EFAULT; - } - - for (i = 0; i < MAX_IOCTL_SGE; i++) { - if (get_user(ptr, &cioc->sgl[i].iov_base) || - put_user(compat_ptr(ptr), &ioc->sgl[i].iov_base) || - copy_in_user(&ioc->sgl[i].iov_len, - &cioc->sgl[i].iov_len, sizeof(compat_size_t))) - return -EFAULT; - } - - error = megasas_mgmt_ioctl_fw(file, (unsigned long)ioc); - - if (copy_in_user(&cioc->frame.hdr.cmd_status, - &ioc->frame.hdr.cmd_status, sizeof(u8))) { - printk(KERN_DEBUG "megasas: error copy_in_user cmd_status\n"); - return -EFAULT; - } - return error; -} - static long megasas_mgmt_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { switch (cmd) { case MEGASAS_IOC_FIRMWARE32: - return megasas_mgmt_compat_ioctl_fw(file, arg); + return megasas_mgmt_ioctl_fw(file, arg); case MEGASAS_IOC_GET_AEN: return megasas_mgmt_ioctl_aen(file, arg); } -- cgit v1.2.3-59-g8ed1b