>From: Olivier Matz [mailto:olivier.matz at 6wind.com] >Sent: Monday, May 02, 2016 3:37 PM >To: Mrzyglod, DanielX T <danielx.t.mrzyglod at intel.com>; dev at dpdk.org >Subject: Re: [PATCH] cmdline: fix unchecked return value > >Hi Daniel, > >On 04/14/2016 03:01 PM, Daniel Mrzyglod wrote: >> This patch is for checking if error values occurs. >> fix for coverity errors #13209 & #13195 >> >> If the function returns an error value, the error value may be mistaken >> for a normal value. >> >> In rdline_char_in: Value returned from a function is not checked for errors >> before being used >> >> Signed-off-by: Daniel Mrzyglod <danielx.t.mrzyglod at intel.com> >> --- >> lib/librte_cmdline/cmdline_rdline.c | 19 +++++++++++++++---- >> 1 file changed, 15 insertions(+), 4 deletions(-) >> >> diff --git a/lib/librte_cmdline/cmdline_rdline.c >b/lib/librte_cmdline/cmdline_rdline.c >> index 1ef2258..e75a556 100644 >> --- a/lib/librte_cmdline/cmdline_rdline.c >> +++ b/lib/librte_cmdline/cmdline_rdline.c >> @@ -377,7 +377,10 @@ rdline_char_in(struct rdline *rdl, char c) >> case CMDLINE_KEY_CTRL_K: >> cirbuf_get_buf_head(&rdl->right, rdl->kill_buf, >RDLINE_BUF_SIZE); >> rdl->kill_size = CIRBUF_GET_LEN(&rdl->right); >> - cirbuf_del_buf_head(&rdl->right, rdl->kill_size); >> + >> + if (cirbuf_del_buf_head(&rdl->right, rdl->kill_size) < >> 0) >> + return -EINVAL; >> + >> rdline_puts(rdl, vt100_clear_right); >> break; >> > >I wonder if a better way to fix wouldn't be to remove the checks >introduced in http://dpdk.org/browse/dpdk/commit/?id=ab971e562860 > >There is no reason to check that in cirbuf_get_buf_head/tail(): > if (!cbuf || !c) > >The function should never fail, it just returns the number of >copied chars. This is the responsibility of the caller to ensure >that the pointer to the circular buffer is not NULL. > >Also, rdline_char_in() is not expected to return -EINVAL, but >RDLINE_RES_* instead. > >So I think that partially revert ab971e562860 would fix the >coverity warning. > >Regards, >Olivier
Removing checks probably will generate more Coverity errors somewhere. I see that only places where we test negative values are in unit tests. Reverting changes I think is overhead and maybe ignoring this patch and set is as false positive in Coverity is better idea ? Regards Daniel
