[PATCH 4.7 29/45] scsi: arcmsr: Buffer overflow in arcmsr_iop_message_xfer()

From: Greg Kroah-Hartman
Date: Fri Oct 21 2016 - 05:40:40 EST


4.7-stable review patch. If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 7bc2b55a5c030685b399bb65b6baa9ccc3d1f167 upstream.

We need to put an upper bound on "user_len" so the memcpy() doesn't
overflow.

Reported-by: Marco Grassi <marco.gra@xxxxxxxxx>
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Tomas Henzl <thenzl@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/scsi/arcmsr/arcmsr_hba.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -2388,7 +2388,8 @@ static int arcmsr_iop_message_xfer(struc
}
case ARCMSR_MESSAGE_WRITE_WQBUFFER: {
unsigned char *ver_addr;
- int32_t user_len, cnt2end;
+ uint32_t user_len;
+ int32_t cnt2end;
uint8_t *pQbuffer, *ptmpuserbuffer;
ver_addr = kmalloc(ARCMSR_API_DATA_BUFLEN, GFP_ATOMIC);
if (!ver_addr) {
@@ -2397,6 +2398,11 @@ static int arcmsr_iop_message_xfer(struc
}
ptmpuserbuffer = ver_addr;
user_len = pcmdmessagefld->cmdmessage.Length;
+ if (user_len > ARCMSR_API_DATA_BUFLEN) {
+ retvalue = ARCMSR_MESSAGE_FAIL;
+ kfree(ver_addr);
+ goto message_out;
+ }
memcpy(ptmpuserbuffer,
pcmdmessagefld->messagedatabuffer, user_len);
spin_lock_irqsave(&acb->wqbuffer_lock, flags);