From 0fbd2cda92cdb00f72080665554a586f88bca821 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Sat, 4 Feb 2023 10:36:52 -0800 Subject: [PATCH] usb: host: xhci: mvebu: Iterate over array indexes instead of using pointer math Walking the dram->cs array was seen as accesses beyond the first array item by the compiler. Instead, use the array index directly. This allows for run-time bounds checking under CONFIG_UBSAN_BOUNDS as well. Seen with GCC 13 with -fstrict-flex-arrays: In function 'xhci_mvebu_mbus_config', inlined from 'xhci_mvebu_mbus_init_quirk' at ../drivers/usb/host/xhci-mvebu.c:66:2: ../drivers/usb/host/xhci-mvebu.c:37:28: warning: array subscript 0 is outside array bounds of 'const struct mbus_dram_window[0]' [-Warray-bounds=] 37 | writel(((cs->size - 1) & 0xffff0000) | (cs->mbus_attr << 8) | | ~~^~~~~~ Cc: Mathias Nyman Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20230204183651.never.663-kees@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-mvebu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci-mvebu.c b/drivers/usb/host/xhci-mvebu.c index 60651a50770f..87f1597a0e5a 100644 --- a/drivers/usb/host/xhci-mvebu.c +++ b/drivers/usb/host/xhci-mvebu.c @@ -32,7 +32,7 @@ static void xhci_mvebu_mbus_config(void __iomem *base, /* Program each DRAM CS in a seperate window */ for (win = 0; win < dram->num_cs; win++) { - const struct mbus_dram_window *cs = dram->cs + win; + const struct mbus_dram_window *cs = &dram->cs[win]; writel(((cs->size - 1) & 0xffff0000) | (cs->mbus_attr << 8) | (dram->mbus_dram_target_id << 4) | 1,