Both the approaches (i.e., using a loop or the strchr()) look fine to me. Thanks, Sudarsana -----Original Message----- From: walter harms [mailto:wharms@xxxxxx] Sent: 16 June 2016 17:50 To: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Cc: Anil Gurumurthy <Anil.Gurumurthy@xxxxxxxxxx>; Sudarsana Kalluru <Sudarsana.Kalluru@xxxxxxxxxx>; James E.J. Bottomley <jejb@xxxxxxxxxxxxxxxxxx>; Martin K. Petersen <martin.petersen@xxxxxxxxxx>; linux-scsi <linux-scsi@xxxxxxxxxxxxxxx>; kernel-janitors@xxxxxxxxxxxxxxx Subject: Re: [patch] bfa: clean up some bounds checking Am 16.06.2016 12:44, schrieb Dan Carpenter: > This code is supposed to search ->adapter_hwpath[] and replace the > second colon with a NUL character. Unfortunately, the boundary checks > that ensure we don't go beyond the end of the buffer have a couple > problems. > > Imagine that the string has no colons. In that case, in the first > loop, we read one space beyond the end of the buffer and then exit the loop. > In the next loop, we increment once, read two characters beyond the > end of the buffer and then exit. Then after the loop we put a NUL > character two characters past the end of the buffer. > > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > --- > This is from static analysis and not tested. Caveat emptor. > > diff --git a/drivers/scsi/bfa/bfad_bsg.c b/drivers/scsi/bfa/bfad_bsg.c > index d1ad020..dfb26f0 100644 > --- a/drivers/scsi/bfa/bfad_bsg.c > +++ b/drivers/scsi/bfa/bfad_bsg.c > @@ -106,10 +106,17 @@ bfad_iocmd_ioc_get_info(struct bfad_s *bfad, > void *cmd) > > /* set adapter hw path */ > strcpy(iocmd->adapter_hwpath, bfad->pci_name); > - for (i = 0; iocmd->adapter_hwpath[i] != ':' && i < BFA_STRING_32; i++) > - ; > - for (; iocmd->adapter_hwpath[++i] != ':' && i < BFA_STRING_32; ) > - ; > + i = -1; > + while (++i < BFA_STRING_32) { > + if (iocmd->adapter_hwpath[i] == ':') > + break; > + } > + while (++i < BFA_STRING_32) { > + if (iocmd->adapter_hwpath[i] == ':') > + break; > + } > + if (i >= BFA_STRING_32) > + i = BFA_STRING_32 - 1; > iocmd->adapter_hwpath[i] = '\0'; > iocmd->status = BFA_STATUS_OK; > return 0; I do not see the use case but i assume the idea is to have a string like aa:bb:something and kill everyhing after the second ':' ? /* a few word may help here also inside the code */ second: maybe we can us strchr here ? s1=strchr(iocmd->adapter_hwpath,':'); if (s1 != NULL ) s1=strchr(s1,":"); re, wh -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
