[PATCH 3.12 71/72] scsi: arcmsr: Buffer overflow in arcmsr_iop_message_xfer()

From: Jiri Slaby
Date: Mon Nov 07 2016 - 08:33:43 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

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

===============

commit 7bc2b55a5c030685b399bb65b6baa9ccc3d1f167 upstream.

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

[js] no ARCMSR_API_DATA_BUFLEN defined, use the number

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: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/scsi/arcmsr/arcmsr_hba.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index 1822cb9ec623..66dda86e62e1 100644
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -1803,7 +1803,8 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,

case ARCMSR_MESSAGE_WRITE_WQBUFFER: {
unsigned char *ver_addr;
- int32_t my_empty_len, user_len, wqbuf_firstindex, wqbuf_lastindex;
+ uint32_t user_len;
+ int32_t my_empty_len, wqbuf_firstindex, wqbuf_lastindex;
uint8_t *pQbuffer, *ptmpuserbuffer;

ver_addr = kmalloc(1032, GFP_ATOMIC);
@@ -1820,6 +1821,11 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,
}
ptmpuserbuffer = ver_addr;
user_len = pcmdmessagefld->cmdmessage.Length;
+ if (user_len > 1032) {
+ retvalue = ARCMSR_MESSAGE_FAIL;
+ kfree(ver_addr);
+ goto message_out;
+ }
memcpy(ptmpuserbuffer, pcmdmessagefld->messagedatabuffer, user_len);
wqbuf_lastindex = acb->wqbuf_lastindex;
wqbuf_firstindex = acb->wqbuf_firstindex;
--
2.10.2