leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

usb: ohci: Prefer struct_size over open coded arithmetic

Browse Source 
As noted in the "Deprecated Interfaces, Language Features, Attributes,
and Conventions" documentation [1], size calculations (especially
multiplication) should not be performed in memory allocator (or similar)
function arguments due to the risk of them overflowing. This could lead
to values wrapping around and a smaller allocation being made than the
caller was expecting. Using those allocations could lead to linear
overflows of heap memory and other misbehaviors.

So, use the struct_size() helper to do the arithmetic instead of the
argument "size + count * size" in the kzalloc() function.

[1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Len Baker <len.baker@gmx.com>
Link: https://lore.kernel.org/r/20210911112631.10004-1-len.baker@gmx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Len Baker
2021-09-11 13:26:31 +02:00
committed by Greg Kroah-Hartman
parent 9c172d4cdf
commit 6943ee7c9d
1 changed files with 1 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/usb/host/ohci-hcd.c
View File

@@ -191,8 +191,7 @@ static int ohci_urb_enqueue (
} }
/* allocate the private part of the URB */ /* allocate the private part of the URB */
urb_priv = kzalloc (sizeof (urb_priv_t) + size * sizeof (struct td *), urb_priv = kzalloc(struct_size(urb_priv, td, size), mem_flags);
mem_flags);
if (!urb_priv) if (!urb_priv)
return -ENOMEM; return -ENOMEM;
INIT_LIST_HEAD (&urb_priv->pending); INIT_LIST_HEAD (&urb_priv->pending);