| Message ID | 20171004075037.j7pkdqqcegvba44e@mwanda (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
Dan, > We could allocate less memory than intended because we do: > > bfad->regdata = kzalloc(len << 2, GFP_KERNEL); > > The shift can overflow leading to a crash. This is debugfs code so the > impact is very small. I fixed the network version of this in March with > commit 13e2d5187f6b ("bna: integer overflow bug in debugfs"). Applied to 4.15/scsi-queue. Thanks!
diff --git a/drivers/scsi/bfa/bfad_debugfs.c b/drivers/scsi/bfa/bfad_debugfs.c index 8dcd8c70c7ee..05f523971348 100644 --- a/drivers/scsi/bfa/bfad_debugfs.c +++ b/drivers/scsi/bfa/bfad_debugfs.c @@ -255,7 +255,8 @@ bfad_debugfs_write_regrd(struct file *file, const char __user *buf, struct bfad_s *bfad = port->bfad; struct bfa_s *bfa = &bfad->bfa; struct bfa_ioc_s *ioc = &bfa->ioc; - int addr, len, rc, i; + int addr, rc, i; + u32 len; u32 *regbuf; void __iomem *rb, *reg_addr; unsigned long flags; @@ -266,7 +267,7 @@ bfad_debugfs_write_regrd(struct file *file, const char __user *buf, return PTR_ERR(kern_buf); rc = sscanf(kern_buf, "%x:%x", &addr, &len); - if (rc < 2) { + if (rc < 2 || len > (UINT_MAX >> 2)) { printk(KERN_INFO "bfad[%d]: %s failed to read user buf\n", bfad->inst_no, __func__);
We could allocate less memory than intended because we do: bfad->regdata = kzalloc(len << 2, GFP_KERNEL); The shift can overflow leading to a crash. This is debugfs code so the impact is very small. I fixed the network version of this in March with commit 13e2d5187f6b ("bna: integer overflow bug in debugfs"). Fixes: ab2a9ba189e8 ("[SCSI] bfa: add debugfs support") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>