From 3577cdb23b8f76612017b82a8a1f89ac55f4d313 Mon Sep 17 00:00:00 2001 From: Len Baker Date: Sat, 25 Sep 2021 16:34:55 +0200 Subject: docs: deprecated.rst: Clarify open-coded arithmetic with literals Although using literals for size calculation in allocator arguments may be harmless due to compiler warnings in case of overflows, it is better to refactor the code to avoid the use of open-coded arithmetic. So, clarify the preferred way in these cases. Suggested-by: Kees Cook Signed-off-by: Len Baker Reviewed-by: Gustavo A. R. Silva Link: https://lore.kernel.org/r/20210925143455.21221-1-len.baker@gmx.com Signed-off-by: Jonathan Corbet --- Documentation/process/deprecated.rst | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'Documentation/process') diff --git a/Documentation/process/deprecated.rst b/Documentation/process/deprecated.rst index 8ced754a5a0f..388cb19f5dbb 100644 --- a/Documentation/process/deprecated.rst +++ b/Documentation/process/deprecated.rst @@ -59,8 +59,9 @@ 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. (One exception to this is literal values where the compiler -can warn if they might overflow. Though using literals for arguments as -suggested below is also harmless.) +can warn if they might overflow. However, the preferred way in these +cases is to refactor the code as suggested below to avoid the open-coded +arithmetic.) For example, do not use ``count * size`` as an argument, as in:: -- cgit v1.2.3