From: Dan Carpenter Date: Mon, 22 Jan 2018 10:23:32 +0000 (+0300) Subject: staging: rts5208: Fix "seg_no" calculation in reset_ms_card() X-Git-Tag: v5.15~9511^2~19 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7f7aeea7cf30368b9fdb86dcc9d2c8a3ebc65dfb;p=platform%2Fkernel%2Flinux-starfive.git staging: rts5208: Fix "seg_no" calculation in reset_ms_card() I get some static checker warnings like this: drivers/staging/rts5208/ms.c:2607 ms_build_l2p_tbl() error: buffer underflow 'ms_card->segment' (-1)-16 The problem is that we memset "ms_card" to zero at the start of the reset_ms_card() function. That means that when we try to calculate "ms_card->total_block / 512 - 1" then it's just always -1. The fix is to calculate "seg_no" before doing the memset(). This is a static checker fix, and I am not able to test it. My theory is that reset_ms_card() gets very little testing which is why this bug exists. Fixes: fa590c222fba ("staging: rts5208: add support for rts5208 and rts5288") Signed-off-by: Dan Carpenter Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/rts5208/ms.c b/drivers/staging/rts5208/ms.c index 7cdce87..821256b 100644 --- a/drivers/staging/rts5208/ms.c +++ b/drivers/staging/rts5208/ms.c @@ -2821,6 +2821,7 @@ BUILD_FAIL: int reset_ms_card(struct rtsx_chip *chip) { struct ms_info *ms_card = &chip->ms_card; + int seg_no = ms_card->total_block / 512 - 1; int retval; memset(ms_card, 0, sizeof(struct ms_info)); @@ -2863,7 +2864,7 @@ int reset_ms_card(struct rtsx_chip *chip) /* Build table for the last segment, * to check if L2P table block exists, erasing it */ - retval = ms_build_l2p_tbl(chip, ms_card->total_block / 512 - 1); + retval = ms_build_l2p_tbl(chip, seg_no); if (retval != STATUS_SUCCESS) { rtsx_trace(chip); return STATUS_FAIL;