From a114af87c0ba390b0146411f89a2a953ffe3c31f Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 4 Oct 2017 10:50:37 +0300 Subject: scsi: bfa: integer overflow in debugfs [ Upstream commit 3e351275655d3c84dc28abf170def9786db5176d ] 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 Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/bfa/bfad_debugfs.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/scsi/bfa/bfad_debugfs.c b/drivers/scsi/bfa/bfad_debugfs.c index 74a307c0a240..8f1c58d4d5b5 100644 --- a/drivers/scsi/bfa/bfad_debugfs.c +++ b/drivers/scsi/bfa/bfad_debugfs.c @@ -254,7 +254,8 @@ 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; @@ -265,7 +266,7 @@ 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__); -- cgit v1.2.3