From: Arseniy Krasnov Date: Wed, 11 Sep 2024 14:24:25 +0000 (+0300) Subject: ASoC: meson: axg-card: fix 'use-after-free' X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=4f9a71435953f941969a4f017e2357db62d85a86;p=linux-block.git ASoC: meson: axg-card: fix 'use-after-free' Buffer 'card->dai_link' is reallocated in 'meson_card_reallocate_links()', so move 'pad' pointer initialization after this function when memory is already reallocated. Kasan bug report: ================================================================== BUG: KASAN: slab-use-after-free in axg_card_add_link+0x76c/0x9bc Read of size 8 at addr ffff000000e8b260 by task modprobe/356 CPU: 0 PID: 356 Comm: modprobe Tainted: G O 6.9.12-sdkernel #1 Call trace: dump_backtrace+0x94/0xec show_stack+0x18/0x24 dump_stack_lvl+0x78/0x90 print_report+0xfc/0x5c0 kasan_report+0xb8/0xfc __asan_load8+0x9c/0xb8 axg_card_add_link+0x76c/0x9bc [snd_soc_meson_axg_sound_card] meson_card_probe+0x344/0x3b8 [snd_soc_meson_card_utils] platform_probe+0x8c/0xf4 really_probe+0x110/0x39c __driver_probe_device+0xb8/0x18c driver_probe_device+0x108/0x1d8 __driver_attach+0xd0/0x25c bus_for_each_dev+0xe0/0x154 driver_attach+0x34/0x44 bus_add_driver+0x134/0x294 driver_register+0xa8/0x1e8 __platform_driver_register+0x44/0x54 axg_card_pdrv_init+0x20/0x1000 [snd_soc_meson_axg_sound_card] do_one_initcall+0xdc/0x25c do_init_module+0x10c/0x334 load_module+0x24c4/0x26cc init_module_from_file+0xd4/0x128 __arm64_sys_finit_module+0x1f4/0x41c invoke_syscall+0x60/0x188 el0_svc_common.constprop.0+0x78/0x13c do_el0_svc+0x30/0x40 el0_svc+0x38/0x78 el0t_64_sync_handler+0x100/0x12c el0t_64_sync+0x190/0x194 Fixes: 7864a79f37b5 ("ASoC: meson: add axg sound card support") Cc: Stable@vger.kernel.org Signed-off-by: Arseniy Krasnov Reviewed-by: Jerome Brunet Link: https://patch.msgid.link/20240911142425.598631-1-avkrasnov@salutedevices.com Signed-off-by: Mark Brown --- diff --git a/sound/soc/meson/axg-card.c b/sound/soc/meson/axg-card.c index 8c5605c1e34e..eb0302f20740 100644 --- a/sound/soc/meson/axg-card.c +++ b/sound/soc/meson/axg-card.c @@ -104,7 +104,7 @@ static int axg_card_add_tdm_loopback(struct snd_soc_card *card, int *index) { struct meson_card *priv = snd_soc_card_get_drvdata(card); - struct snd_soc_dai_link *pad = &card->dai_link[*index]; + struct snd_soc_dai_link *pad; struct snd_soc_dai_link *lb; struct snd_soc_dai_link_component *dlc; int ret; @@ -114,6 +114,7 @@ static int axg_card_add_tdm_loopback(struct snd_soc_card *card, if (ret) return ret; + pad = &card->dai_link[*index]; lb = &card->dai_link[*index + 1]; lb->name = devm_kasprintf(card->dev, GFP_KERNEL, "%s-lb", pad->name);