From eccbf04a904fc99c54ab37c29a2a4dedcec66e33 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 21 Oct 2010 07:46:58 +0200 Subject: [PATCH] Staging: bcm: use get_user() to access user pointers This fixes some places that dereference user pointers directly instead of using get_user(). Please especially check my changes to IOCTL_BCM_GET_CURRENT_STATUS. The original code modified the struct which "arg" was pointing to. I think this was a bug in the original code and that we only wanted to write to the OutputBuffer. Also with the original code you could read as much memory as you wanted so I had to put a cap on OutputLength. The only value of OutputLength that makes sense is sizeof(LINK_STATE) so now if OutputLength is not sizeof(LINK_STATE) it returns -EINVAL. Signed-off-by: Dan Carpenter Signed-off-by: Greg Kroah-Hartman --- drivers/staging/bcm/Bcmchar.c | 49 +++++++++++++++++++++++------------ 1 file changed, 32 insertions(+), 17 deletions(-) diff --git a/drivers/staging/bcm/Bcmchar.c b/drivers/staging/bcm/Bcmchar.c index 77fdfe24d999..fead9c56162e 100644 --- a/drivers/staging/bcm/Bcmchar.c +++ b/drivers/staging/bcm/Bcmchar.c @@ -1001,13 +1001,15 @@ static long bcm_char_ioctl(struct file *filp, UINT cmd, ULONG arg) } #endif case IOCTL_BE_BUCKET_SIZE: - Adapter->BEBucketSize = *(PULONG)arg; - Status = STATUS_SUCCESS; + Status = 0; + if (get_user(Adapter->BEBucketSize, (unsigned long __user *)arg)) + Status = -EFAULT; break; case IOCTL_RTPS_BUCKET_SIZE: - Adapter->rtPSBucketSize = *(PULONG)arg; - Status = STATUS_SUCCESS; + Status = 0; + if (get_user(Adapter->rtPSBucketSize, (unsigned long __user *)arg)) + Status = -EFAULT; break; case IOCTL_CHIP_RESET: { @@ -1028,11 +1030,15 @@ static long bcm_char_ioctl(struct file *filp, UINT cmd, ULONG arg) case IOCTL_QOS_THRESHOLD: { USHORT uiLoopIndex; - for(uiLoopIndex = 0 ; uiLoopIndex < NO_OF_QUEUES ; uiLoopIndex++) - { - Adapter->PackInfo[uiLoopIndex].uiThreshold = *(PULONG)arg; + + Status = 0; + for (uiLoopIndex = 0; uiLoopIndex < NO_OF_QUEUES; uiLoopIndex++) { + if (get_user(Adapter->PackInfo[uiLoopIndex].uiThreshold, + (unsigned long __user *)arg)) { + Status = -EFAULT; + break; + } } - Status = STATUS_SUCCESS; break; } @@ -1093,7 +1099,8 @@ static long bcm_char_ioctl(struct file *filp, UINT cmd, ULONG arg) } case IOCTL_BCM_GET_CURRENT_STATUS: { - LINK_STATE *plink_state = NULL; + LINK_STATE plink_state; + /* Copy Ioctl Buffer structure */ if(copy_from_user(&IoBuffer, argp, sizeof(IOCTL_BUFFER))) { @@ -1101,13 +1108,19 @@ static long bcm_char_ioctl(struct file *filp, UINT cmd, ULONG arg) Status = -EFAULT; break; } - plink_state = (LINK_STATE*)arg; - plink_state->bIdleMode = (UCHAR)Adapter->IdleMode; - plink_state->bShutdownMode = Adapter->bShutStatus; - plink_state->ucLinkStatus = (UCHAR)Adapter->LinkStatus; - if(copy_to_user(IoBuffer.OutputBuffer, - (PUCHAR)plink_state, (UINT)IoBuffer.OutputLength)) - { + if (IoBuffer.OutputLength != sizeof(plink_state)) { + Status = -EINVAL; + break; + } + + if (copy_from_user(&plink_state, (void __user *)arg, sizeof(plink_state))) { + Status = -EFAULT; + break; + } + plink_state.bIdleMode = (UCHAR)Adapter->IdleMode; + plink_state.bShutdownMode = Adapter->bShutStatus; + plink_state.ucLinkStatus = (UCHAR)Adapter->LinkStatus; + if (copy_to_user(IoBuffer.OutputBuffer, &plink_state, IoBuffer.OutputLength)) { BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0, "Copy_to_user Failed..\n"); Status = -EFAULT; break; @@ -1331,7 +1344,9 @@ static long bcm_char_ioctl(struct file *filp, UINT cmd, ULONG arg) BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0,"Copy From User space failed. status :%d", Status); return -EFAULT; } - uiSectorSize = *((PUINT)(IoBuffer.InputBuffer)); /* FIXME: unchecked __user access */ + if (get_user(uiSectorSize, (unsigned int __user *)IoBuffer.InputBuffer)) + return -EFAULT; + if((uiSectorSize < MIN_SECTOR_SIZE) || (uiSectorSize > MAX_SECTOR_SIZE)) { -- 2.20.1