From dc03f05e419f3460342fb7564884f244622634b6 Mon Sep 17 00:00:00 2001 From: Muhammad Bilal Date: Wed, 12 Aug 2026 16:18:21 +0500 Subject: [PATCH] platform/x86: hp-bioscfg: fix off-by-one write in hp_get_string_from_buffer() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit hp_get_string_from_buffer() clamps the converted string length against the destination buffer size with "size > dst_size", so when the converted length is exactly equal to dst_size, conv_dst_size is left at dst_size and the unconditional NUL terminator write dst[conv_dst_size] = 0; lands one byte past the destination buffer. This is the same shape of bug as the previously fixed off-by-one in hp_convert_hexstr_to_str(): the buffer is sized correctly for the content, but the terminator write is never checked against that size. Fix by changing the comparison to ">=" so conv_dst_size is always left with room for the terminator. All fixed-size destinations that reach this function (path[512], current_value[512], current_password/current_value[64], and the per-entry buffers in encodings[][512] and prerequisites[][512]) are affected. Fixes: a34fc329b189 ("platform/x86: hp-bioscfg: bioscfg") Cc: stable@vger.kernel.org Signed-off-by: Muhammad Bilal Link: https://patch.msgid.link/20260812111829.172273-2-meatuni001@gmail.com Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen --- drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c index 78019644ec35..309634c1cc20 100644 --- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c +++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c @@ -85,7 +85,7 @@ int hp_get_string_from_buffer(u8 **buffer, u32 *buffer_size, char *dst, u32 dst_ * bytes. */ conv_dst_size = size; - if (size > dst_size) + if (size >= dst_size) conv_dst_size = dst_size - 1; /*