From d5872e93fab99e371de97537d7f352cecdf7f92e Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Sat, 4 Feb 2023 19:36:17 +0100 Subject: [PATCH] media: mxl5005s: Bounds check size used for max array index The use of state->CH_Ctrl[i].size in a shift operation implies that its value can be as much as 32, but the state->CH_Ctrl[i].val array is only 25 in size. Bounds check the size before shifting and looping. Fixes warnings seen with GCC 13: ../drivers/media/tuners/mxl5005s.c: In function 'MXL_ControlWrite_Group.isra': ../drivers/media/tuners/mxl5005s.c:3450:70: warning: array subscript 32 is above array bounds of 'u16[25]' {aka 'short unsigned int[25]'} [-Warray-bounds=] 3450 | state->CH_Ctrl[i].val[j] = (u8)((value >> j) & 0x01); | ~~~~~~~~~~~~~~~~~~~~~^~~ ../drivers/media/tuners/mxl5005s.c:238:13: note: while referencing 'val' 238 | u16 val[25]; /* Binary representation of Value */ | ^~~ Cc: Colin Ian King Signed-off-by: Kees Cook Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/tuners/mxl5005s.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/media/tuners/mxl5005s.c b/drivers/media/tuners/mxl5005s.c index 3a509038c8df..06dfab9fb8cb 100644 --- a/drivers/media/tuners/mxl5005s.c +++ b/drivers/media/tuners/mxl5005s.c @@ -3423,9 +3423,11 @@ static u16 MXL_ControlWrite_Group(struct dvb_frontend *fe, u16 controlNum, if (controlNum == state->Init_Ctrl[i].Ctrl_Num) { - highLimit = 1 << state->Init_Ctrl[i].size; + u16 size = min_t(u16, state->Init_Ctrl[i].size, + ARRAY_SIZE(state->Init_Ctrl[i].val)); + highLimit = 1 << size; if (value < highLimit) { - for (j = 0; j < state->Init_Ctrl[i].size; j++) { + for (j = 0; j < size; j++) { state->Init_Ctrl[i].val[j] = (u8)((value >> j) & 0x01); MXL_RegWriteBit(fe, (u8)(state->Init_Ctrl[i].addr[j]), (u8)(state->Init_Ctrl[i].bit[j]), @@ -3442,9 +3444,11 @@ static u16 MXL_ControlWrite_Group(struct dvb_frontend *fe, u16 controlNum, if (controlNum == state->CH_Ctrl[i].Ctrl_Num) { - highLimit = 1 << state->CH_Ctrl[i].size; + u16 size = min_t(u16, state->CH_Ctrl[i].size, + ARRAY_SIZE(state->CH_Ctrl[i].val)); + highLimit = 1 << size; if (value < highLimit) { - for (j = 0; j < state->CH_Ctrl[i].size; j++) { + for (j = 0; j < size; j++) { state->CH_Ctrl[i].val[j] = (u8)((value >> j) & 0x01); MXL_RegWriteBit(fe, (u8)(state->CH_Ctrl[i].addr[j]), (u8)(state->CH_Ctrl[i].bit[j]),