Patch "ASoC: kirkwood: Iterate over array indexes instead of using pointer math" has been added to the 6.1-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ASoC: kirkwood: Iterate over array indexes instead of using pointer math

to the 6.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     asoc-kirkwood-iterate-over-array-indexes-instead-of-.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit a27b5ab908775a3f28ff4a2e5f5c071e2da99a57
Author: Kees Cook <keescook@xxxxxxxxxxxx>
Date:   Fri Jan 27 14:41:29 2023 -0800

    ASoC: kirkwood: Iterate over array indexes instead of using pointer math
    
    [ Upstream commit b3bcedc0402fcdc5c8624c433562d9d1882749d8 ]
    
    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:
    
    ../sound/soc/kirkwood/kirkwood-dma.c: In function
    'kirkwood_dma_conf_mbus_windows.constprop':
    ../sound/soc/kirkwood/kirkwood-dma.c:90:24: warning: array subscript 0 is outside array bounds of 'const struct mbus_dram_window[0]' [-Warray-bounds=]
       90 |                 if ((cs->base & 0xffff0000) < (dma & 0xffff0000)) {
          |                      ~~^~~~~~
    
    Cc: Liam Girdwood <lgirdwood@xxxxxxxxx>
    Cc: Mark Brown <broonie@xxxxxxxxxx>
    Cc: Jaroslav Kysela <perex@xxxxxxxx>
    Cc: Takashi Iwai <tiwai@xxxxxxxx>
    Cc: alsa-devel@xxxxxxxxxxxxxxxx
    Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20230127224128.never.410-kees@xxxxxxxxxx
    Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/sound/soc/kirkwood/kirkwood-dma.c b/sound/soc/kirkwood/kirkwood-dma.c
index 700a18561a940..640cebd2983e2 100644
--- a/sound/soc/kirkwood/kirkwood-dma.c
+++ b/sound/soc/kirkwood/kirkwood-dma.c
@@ -86,7 +86,7 @@ kirkwood_dma_conf_mbus_windows(void __iomem *base, int win,
 
 	/* try to find matching cs for current dma address */
 	for (i = 0; i < dram->num_cs; i++) {
-		const struct mbus_dram_window *cs = dram->cs + i;
+		const struct mbus_dram_window *cs = &dram->cs[i];
 		if ((cs->base & 0xffff0000) < (dma & 0xffff0000)) {
 			writel(cs->base & 0xffff0000,
 				base + KIRKWOOD_AUDIO_WIN_BASE_REG(win));