| Message ID | 20210905062448.6587-1-len.baker@gmx.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | scsi: elx: libefc: Prefer kcalloc over open coded arithmetic | expand |
On 9/4/2021 11:24 PM, Len Baker wrote: > 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 purpose specific kcalloc() function instead of the argument > count * size in the kzalloc() function. > > [1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments > > Signed-off-by: Len Baker <len.baker@gmx.com> Looks good. Thanks Reviewed-by: James Smart <jsmart2021@gmail.com> -- james
On Sun, 5 Sep 2021 08:24:48 +0200, Len Baker wrote: > 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. > > [...] Applied to 5.16/scsi-queue, thanks! [1/1] scsi: elx: libefc: Prefer kcalloc over open coded arithmetic https://git.kernel.org/mkp/scsi/c/0a5e20fc8ca7
diff --git a/drivers/scsi/elx/libefc/efc_fabric.c b/drivers/scsi/elx/libefc/efc_fabric.c index d397220d9e54..f9412437ad47 100644 --- a/drivers/scsi/elx/libefc/efc_fabric.c +++ b/drivers/scsi/elx/libefc/efc_fabric.c @@ -686,7 +686,7 @@ efc_process_gidpt_payload(struct efc_node *node, } /* Allocate a buffer for all nodes */ - active_nodes = kzalloc(port_count * sizeof(*active_nodes), GFP_ATOMIC); + active_nodes = kcalloc(port_count, sizeof(*active_nodes), GFP_ATOMIC); if (!active_nodes) { node_printf(node, "efc_malloc failed\n"); return -EIO;
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 purpose specific kcalloc() function instead of the argument count * size in the kzalloc() function. [1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments Signed-off-by: Len Baker <len.baker@gmx.com> --- drivers/scsi/elx/libefc/efc_fabric.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.25.1