From 90e8f2db60a1e49526f053876925741682da96ab Mon Sep 17 00:00:00 2001 From: Ashok Reddy Soma Date: Wed, 23 Feb 2022 15:00:57 +0100 Subject: [PATCH] fru: ops: Return error from checksum if data is all zero's fru_checksum function is simply adding all the bytes and returning the sum. If the data passed to this function is all zero's then it will return 0, and the functions calling this api will assume that checksum is correct. Ideally this is not good. Fix this by returning error if all the data is 0's. Signed-off-by: Ashok Reddy Soma Signed-off-by: Michal Simek Link: https://lore.kernel.org/r/ac0366fe55c60a818a3f9ed33d96826c817d5520.1645624855.git.michal.simek@xilinx.com --- board/xilinx/common/fru_ops.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/board/xilinx/common/fru_ops.c b/board/xilinx/common/fru_ops.c index a0a1441..058e750 100644 --- a/board/xilinx/common/fru_ops.c +++ b/board/xilinx/common/fru_ops.c @@ -39,12 +39,20 @@ static int fru_check_language(u8 code) u8 fru_checksum(u8 *addr, u8 len) { u8 checksum = 0; + u8 cnt = len; while (len--) { + if (*addr == 0) + cnt--; + checksum += *addr; addr++; } + /* If all data bytes are 0's return error */ + if (!cnt) + return EINVAL; + return checksum; } -- 2.7.4