From 8ebe2607965d3e2dc02029e8c7dd35fbe508ffd0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
Date: Mon, 27 Jul 2020 15:38:34 +0200
Subject: [PATCH] mmc: sdio: Check for CISTPL_VERS_1 buffer size
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Git-commit: 8ebe2607965d3e2dc02029e8c7dd35fbe508ffd0
Patch-mainline: v5.10-rc1
References: git-fixes
Before parsing CISTPL_VERS_1 structure check that its size is at least two
bytes to prevent buffer overflow.
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20200727133837.19086-2-pali@kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/mmc/core/sdio_cis.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
index e0655278c5c3..3efaa9534a77 100644
--- a/drivers/mmc/core/sdio_cis.c
+++ b/drivers/mmc/core/sdio_cis.c
@@ -26,6 +26,9 @@ static int cistpl_vers_1(struct mmc_card *card, struct sdio_func *func,
unsigned i, nr_strings;
char **buffer, *string;
+ if (size < 2)
+ return 0;
+
/* Find all null-terminated (including zero length) strings in
the TPLLV1_INFO field. Trailing garbage is ignored. */
buf += 2;
--
2.16.4