From e47029b977e747cb3a9174308fd55762cce70147 Mon Sep 17 00:00:00 2001 From: Tudor Ambarus Date: Fri, 17 Apr 2026 15:24:39 +0000 Subject: [PATCH] mtd: spi-nor: debugfs: fix out-of-bounds read in spi_nor_params_show() Sashiko noticed an out-of-bounds read [1]. In spi_nor_params_show(), the snor_f_names array is passed to spi_nor_print_flags() using sizeof(snor_f_names). Since snor_f_names is an array of pointers, sizeof() returns the total number of bytes occupied by the pointers (element_count * sizeof(void *)) rather than the element count itself. On 64-bit systems, this makes the passed length 8x larger than intended. Inside spi_nor_print_flags(), the 'names_len' argument is used to bounds-check the 'names' array access. An out-of-bounds read occurs if a flag bit is set that exceeds the array's actual element count but is within the inflated byte-size count. Correct this by using ARRAY_SIZE() to pass the actual number of string pointers in the array. Cc: stable@vger.kernel.org Fixes: 0257be79fc4a ("mtd: spi-nor: expose internal parameters via debugfs") Closes: https://sashiko.dev/#/patchset/20260417-die-erase-fix-v2-1-73bb7004ebad%40infineon.com [1] Signed-off-by: Tudor Ambarus Reviewed-by: Takahiro Kuwano Reviewed-by: Michael Walle Reviewed-by: Pratyush Yadav Signed-off-by: Miquel Raynal --- drivers/mtd/spi-nor/debugfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/spi-nor/debugfs.c b/drivers/mtd/spi-nor/debugfs.c index fa6956144d2e..14ba1680c315 100644 --- a/drivers/mtd/spi-nor/debugfs.c +++ b/drivers/mtd/spi-nor/debugfs.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 +#include #include #include #include @@ -92,7 +93,8 @@ static int spi_nor_params_show(struct seq_file *s, void *data) seq_printf(s, "address nbytes\t%u\n", nor->addr_nbytes); seq_puts(s, "flags\t\t"); - spi_nor_print_flags(s, nor->flags, snor_f_names, sizeof(snor_f_names)); + spi_nor_print_flags(s, nor->flags, snor_f_names, + ARRAY_SIZE(snor_f_names)); seq_puts(s, "\n"); seq_puts(s, "\nopcodes\n");