| Message ID | 20200706130820.487271-1-colin.king@canonical.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [next] scsi: lpfc: fix less than zero comparison on unsigned int computation | expand |
On 7/6/2020 6:08 AM, Colin King wrote: > From: Colin Ian King <colin.king@canonical.com> > > The expressions start_idx - dbg_cnt is evaluated using unsigned int > arthithmetic (since these variables are unsigned ints) and hence can > never be less than zero, so the less than comparison is never true. > Re-write the expression to check for start_idx being less than dbg_cnt. > > Addresses-Coverity: ("Unsigned compared against 0") > Fixes: 372c187b8a70 ("scsi: lpfc: Add an internal trace log buffer") > Signed-off-by: Colin Ian King <colin.king@canonical.com> > --- > drivers/scsi/lpfc/lpfc_init.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c > index 7285b0114837..ce5afe7b11d0 100644 > --- a/drivers/scsi/lpfc/lpfc_init.c > +++ b/drivers/scsi/lpfc/lpfc_init.c > @@ -14152,7 +14152,7 @@ void lpfc_dmp_dbg(struct lpfc_hba *phba) > if ((start_idx + dbg_cnt) > (DBG_LOG_SZ - 1)) { > temp_idx = (start_idx + dbg_cnt) % DBG_LOG_SZ; > } else { > - if ((start_idx - dbg_cnt) < 0) { > + if (start_idx < dbg_cnt) { > start_idx = DBG_LOG_SZ - (dbg_cnt - start_idx); > temp_idx = 0; > } else { Thanks Colin - I was about to send a patch for this. Has this fix and one a couple of lines further down. I will post it shortly. -- james
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c index 7285b0114837..ce5afe7b11d0 100644 --- a/drivers/scsi/lpfc/lpfc_init.c +++ b/drivers/scsi/lpfc/lpfc_init.c @@ -14152,7 +14152,7 @@ void lpfc_dmp_dbg(struct lpfc_hba *phba) if ((start_idx + dbg_cnt) > (DBG_LOG_SZ - 1)) { temp_idx = (start_idx + dbg_cnt) % DBG_LOG_SZ; } else { - if ((start_idx - dbg_cnt) < 0) { + if (start_idx < dbg_cnt) { start_idx = DBG_LOG_SZ - (dbg_cnt - start_idx); temp_idx = 0; } else {