The following commit has been merged into the x86/platform branch of tip: Commit-ID: a0947081af2ac9549e6ba19877456730713bde23 Gitweb: https://git.kernel.org/tip/a0947081af2ac9549e6ba19877456730713bde23 Author: Gustavo A. R. Silva <[email protected]> AuthorDate: Thu, 01 Oct 2020 09:56:08 -05:00 Committer: Borislav Petkov <[email protected]> CommitterDate: Thu, 01 Oct 2020 18:47:39 +02:00
x86/uv/time: Use a flexible array in struct uv_rtc_timer_head There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. struct uv_rtc_timer_head contains a one-element array cpu[1]. Switch it to a flexible array and use the struct_size() helper to calculate the allocation size. Also, save some heap space in the process[3]. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays [3] https://lore.kernel.org/lkml/20200518190114.GA7757@embeddedor/ [ bp: Massage a bit. ] Signed-off-by: Gustavo A. R. Silva <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Kees Cook <[email protected]> Cc: Steve Wahl <[email protected]> Link: https://lkml.kernel.org/r/20201001145608.GA10204@embeddedor --- arch/x86/platform/uv/uv_time.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/arch/x86/platform/uv/uv_time.c b/arch/x86/platform/uv/uv_time.c index f82a133..6c348c2 100644 --- a/arch/x86/platform/uv/uv_time.c +++ b/arch/x86/platform/uv/uv_time.c @@ -52,7 +52,7 @@ struct uv_rtc_timer_head { struct { int lcpu; /* systemwide logical cpu number */ u64 expires; /* next timer expiration for this cpu */ - } cpu[1]; + } cpu[]; }; /* @@ -148,9 +148,8 @@ static __init int uv_rtc_allocate_timers(void) struct uv_rtc_timer_head *head = blade_info[bid]; if (!head) { - head = kmalloc_node(sizeof(struct uv_rtc_timer_head) + - (uv_blade_nr_possible_cpus(bid) * - 2 * sizeof(u64)), + head = kmalloc_node(struct_size(head, cpu, + uv_blade_nr_possible_cpus(bid)), GFP_KERNEL, nid); if (!head) { uv_rtc_deallocate_timers();
