This parameters are not changed after early boot. By making them __ro_after_init will reduce any attack surface in the kernel.
Link: https://lwn.net/Articles/676145/ Cc: Christoph Hellwig <h...@lst.de> Cc: Marek Szyprowski <m.szyprow...@samsung.com> Cc: Robin Murphy <robin.mur...@arm.com> Cc: Matthew Wilcox <wi...@infradead.org> Cc: Christopher Lameter <c...@linux.com> Cc: Kees Cook <keesc...@chromium.org> Signed-off-by: Shyam Saini <mayhs11sa...@gmail.com> --- kernel/dma/contiguous.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index 69cfb4345388..1b689b1303cd 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -42,10 +42,10 @@ struct cma *dma_contiguous_default_area; * Users, who want to set the size of global CMA area for their system * should use cma= kernel parameter. */ -static const phys_addr_t size_bytes = (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M; -static phys_addr_t size_cmdline = -1; -static phys_addr_t base_cmdline; -static phys_addr_t limit_cmdline; +static const phys_addr_t __ro_after_init size_bytes = (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M; +static phys_addr_t __ro_after_init size_cmdline = -1; +static phys_addr_t __ro_after_init base_cmdline; +static phys_addr_t __ro_after_init limit_cmdline; static int __init early_cma(char *p) { -- 2.20.1
