| Message ID | 1473755277-23489-1-git-send-email-haibo.chen@nxp.com |
|---|---|
| State | Changes Requested |
| Delegated to: | Tom Rini |
| Headers | show |
On Tue, Sep 13, 2016 at 04:27:57PM +0800, Haibo Chen wrote: > Suspicious implicit sign extension exist. ext_csd[] is defined > as "u8", capacity is defined as u64, so u8 is promoted to signed > int first int the "|" expersion, then the sign extended to u64. > if the tmp sign value is largeer than 0x7fffffff, after the sign > extension, the upper bits of the result will all be 1. > Thanks to coverity <http://www.coverity.com> > > e.g. > u8 data_8; > u64 data_64; > > data_8 = 0x80; > data_64 = data_8 << 24; //0xffffffff80000000 > data_64 = ((u64)data_8) << 24; //0x80000000 > > Signed-off-by: Haibo Chen <haibo.chen@nxp.com> Please add a 'Reported-by: Coverity' and you can include the CID if you like. > --- > drivers/mmc/mmc.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c > index 43ea0bb..c1d1dc6 100644 > --- a/drivers/mmc/mmc.c > +++ b/drivers/mmc/mmc.c > @@ -1176,10 +1176,10 @@ static int mmc_startup(struct mmc *mmc) > * ext_csd's capacity is valid if the value is more > * than 2GB > */ > - capacity = ext_csd[EXT_CSD_SEC_CNT] << 0 > - | ext_csd[EXT_CSD_SEC_CNT + 1] << 8 > - | ext_csd[EXT_CSD_SEC_CNT + 2] << 16 > - | ext_csd[EXT_CSD_SEC_CNT + 3] << 24; > + capacity = ((u64)ext_csd[EXT_CSD_SEC_CNT]) << 0 > + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 1]) << 8 > + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 2]) << 16 > + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 3]) << 24; > capacity *= MMC_MAX_BLOCK_LEN; > if ((capacity >> 20) > 2 * 1024) > mmc->capacity_user = capacity; Can't we just move capacity down to a u8 instead? Thanks!
On 09/19/2016 02:53 AM, Tom Rini wrote: > On Tue, Sep 13, 2016 at 04:27:57PM +0800, Haibo Chen wrote: > >> Suspicious implicit sign extension exist. ext_csd[] is defined >> as "u8", capacity is defined as u64, so u8 is promoted to signed >> int first int the "|" expersion, then the sign extended to u64. >> if the tmp sign value is largeer than 0x7fffffff, after the sign >> extension, the upper bits of the result will all be 1. >> Thanks to coverity <http://www.coverity.com> >> >> e.g. >> u8 data_8; >> u64 data_64; >> >> data_8 = 0x80; >> data_64 = data_8 << 24; //0xffffffff80000000 >> data_64 = ((u64)data_8) << 24; //0x80000000 >> >> Signed-off-by: Haibo Chen <haibo.chen@nxp.com> > > Please add a 'Reported-by: Coverity' and you can include the CID if you > like. I think cid doesn't need to change type. > >> --- >> drivers/mmc/mmc.c | 8 ++++---- >> 1 file changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c >> index 43ea0bb..c1d1dc6 100644 >> --- a/drivers/mmc/mmc.c >> +++ b/drivers/mmc/mmc.c >> @@ -1176,10 +1176,10 @@ static int mmc_startup(struct mmc *mmc) >> * ext_csd's capacity is valid if the value is more >> * than 2GB >> */ >> - capacity = ext_csd[EXT_CSD_SEC_CNT] << 0 >> - | ext_csd[EXT_CSD_SEC_CNT + 1] << 8 >> - | ext_csd[EXT_CSD_SEC_CNT + 2] << 16 >> - | ext_csd[EXT_CSD_SEC_CNT + 3] << 24; >> + capacity = ((u64)ext_csd[EXT_CSD_SEC_CNT]) << 0 >> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 1]) << 8 >> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 2]) << 16 >> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 3]) << 24; >> capacity *= MMC_MAX_BLOCK_LEN; >> if ((capacity >> 20) > 2 * 1024) >> mmc->capacity_user = capacity; > > Can't we just move capacity down to a u8 instead? Thanks! Maybe not to move down to a u8..because it's displayed the real capacity for storage. And i wonder that coverity didn't report about the line 1294? Best Regards, Jaehoon Chung > > > > _______________________________________________ > U-Boot mailing list > U-Boot@lists.denx.de > http://lists.denx.de/mailman/listinfo/u-boot >
On Mon, Sep 19, 2016 at 03:31:54PM +0900, Jaehoon Chung wrote: > On 09/19/2016 02:53 AM, Tom Rini wrote: > > On Tue, Sep 13, 2016 at 04:27:57PM +0800, Haibo Chen wrote: > > > >> Suspicious implicit sign extension exist. ext_csd[] is defined > >> as "u8", capacity is defined as u64, so u8 is promoted to signed > >> int first int the "|" expersion, then the sign extended to u64. > >> if the tmp sign value is largeer than 0x7fffffff, after the sign > >> extension, the upper bits of the result will all be 1. > >> Thanks to coverity <http://www.coverity.com> > >> > >> e.g. > >> u8 data_8; > >> u64 data_64; > >> > >> data_8 = 0x80; > >> data_64 = data_8 << 24; //0xffffffff80000000 > >> data_64 = ((u64)data_8) << 24; //0x80000000 > >> > >> Signed-off-by: Haibo Chen <haibo.chen@nxp.com> > > > > Please add a 'Reported-by: Coverity' and you can include the CID if you > > like. > > I think cid doesn't need to change type. I mean the coverity CID :) In the public coverity project it's 149300 > > > > >> --- > >> drivers/mmc/mmc.c | 8 ++++---- > >> 1 file changed, 4 insertions(+), 4 deletions(-) > >> > >> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c > >> index 43ea0bb..c1d1dc6 100644 > >> --- a/drivers/mmc/mmc.c > >> +++ b/drivers/mmc/mmc.c > >> @@ -1176,10 +1176,10 @@ static int mmc_startup(struct mmc *mmc) > >> * ext_csd's capacity is valid if the value is more > >> * than 2GB > >> */ > >> - capacity = ext_csd[EXT_CSD_SEC_CNT] << 0 > >> - | ext_csd[EXT_CSD_SEC_CNT + 1] << 8 > >> - | ext_csd[EXT_CSD_SEC_CNT + 2] << 16 > >> - | ext_csd[EXT_CSD_SEC_CNT + 3] << 24; > >> + capacity = ((u64)ext_csd[EXT_CSD_SEC_CNT]) << 0 > >> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 1]) << 8 > >> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 2]) << 16 > >> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 3]) << 24; > >> capacity *= MMC_MAX_BLOCK_LEN; > >> if ((capacity >> 20) > 2 * 1024) > >> mmc->capacity_user = capacity; > > > > Can't we just move capacity down to a u8 instead? Thanks! > > Maybe not to move down to a u8..because it's displayed the real capacity for storage. We could update those lines too? It's just that one case right there, yes? > And i wonder that coverity didn't report about the line 1294? It does, along with 1256. Thanks!
On 09/19/2016 08:30 PM, Tom Rini wrote: > On Mon, Sep 19, 2016 at 03:31:54PM +0900, Jaehoon Chung wrote: >> On 09/19/2016 02:53 AM, Tom Rini wrote: >>> On Tue, Sep 13, 2016 at 04:27:57PM +0800, Haibo Chen wrote: >>> >>>> Suspicious implicit sign extension exist. ext_csd[] is defined >>>> as "u8", capacity is defined as u64, so u8 is promoted to signed >>>> int first int the "|" expersion, then the sign extended to u64. >>>> if the tmp sign value is largeer than 0x7fffffff, after the sign >>>> extension, the upper bits of the result will all be 1. >>>> Thanks to coverity <http://www.coverity.com> >>>> >>>> e.g. >>>> u8 data_8; >>>> u64 data_64; >>>> >>>> data_8 = 0x80; >>>> data_64 = data_8 << 24; //0xffffffff80000000 >>>> data_64 = ((u64)data_8) << 24; //0x80000000 >>>> >>>> Signed-off-by: Haibo Chen <haibo.chen@nxp.com> >>> >>> Please add a 'Reported-by: Coverity' and you can include the CID if you >>> like. >> >> I think cid doesn't need to change type. > > I mean the coverity CID :) In the public coverity project it's 149300 Ah! I misunderstood CID as cid register. :) > >> >>> >>>> --- >>>> drivers/mmc/mmc.c | 8 ++++---- >>>> 1 file changed, 4 insertions(+), 4 deletions(-) >>>> >>>> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c >>>> index 43ea0bb..c1d1dc6 100644 >>>> --- a/drivers/mmc/mmc.c >>>> +++ b/drivers/mmc/mmc.c >>>> @@ -1176,10 +1176,10 @@ static int mmc_startup(struct mmc *mmc) >>>> * ext_csd's capacity is valid if the value is more >>>> * than 2GB >>>> */ >>>> - capacity = ext_csd[EXT_CSD_SEC_CNT] << 0 >>>> - | ext_csd[EXT_CSD_SEC_CNT + 1] << 8 >>>> - | ext_csd[EXT_CSD_SEC_CNT + 2] << 16 >>>> - | ext_csd[EXT_CSD_SEC_CNT + 3] << 24; >>>> + capacity = ((u64)ext_csd[EXT_CSD_SEC_CNT]) << 0 >>>> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 1]) << 8 >>>> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 2]) << 16 >>>> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 3]) << 24; >>>> capacity *= MMC_MAX_BLOCK_LEN; >>>> if ((capacity >> 20) > 2 * 1024) >>>> mmc->capacity_user = capacity; >>> >>> Can't we just move capacity down to a u8 instead? Thanks! >> >> Maybe not to move down to a u8..because it's displayed the real capacity for storage. > > We could update those lines too? It's just that one case right there, > yes? If it's possible to calculate the correct capacity? Best Regards, Jaehoon Chung > >> And i wonder that coverity didn't report about the line 1294? > > It does, along with 1256. > > Thanks! >
On Tue, Sep 20, 2016 at 11:04:40AM +0900, Jaehoon Chung wrote: > On 09/19/2016 08:30 PM, Tom Rini wrote: > > On Mon, Sep 19, 2016 at 03:31:54PM +0900, Jaehoon Chung wrote: > >> On 09/19/2016 02:53 AM, Tom Rini wrote: > >>> On Tue, Sep 13, 2016 at 04:27:57PM +0800, Haibo Chen wrote: > >>> > >>>> Suspicious implicit sign extension exist. ext_csd[] is defined > >>>> as "u8", capacity is defined as u64, so u8 is promoted to signed > >>>> int first int the "|" expersion, then the sign extended to u64. > >>>> if the tmp sign value is largeer than 0x7fffffff, after the sign > >>>> extension, the upper bits of the result will all be 1. > >>>> Thanks to coverity <http://www.coverity.com> > >>>> > >>>> e.g. > >>>> u8 data_8; > >>>> u64 data_64; > >>>> > >>>> data_8 = 0x80; > >>>> data_64 = data_8 << 24; //0xffffffff80000000 > >>>> data_64 = ((u64)data_8) << 24; //0x80000000 > >>>> > >>>> Signed-off-by: Haibo Chen <haibo.chen@nxp.com> > >>> > >>> Please add a 'Reported-by: Coverity' and you can include the CID if you > >>> like. > >> > >> I think cid doesn't need to change type. > > > > I mean the coverity CID :) In the public coverity project it's 149300 > > Ah! I misunderstood CID as cid register. :) > > > > >> > >>> > >>>> --- > >>>> drivers/mmc/mmc.c | 8 ++++---- > >>>> 1 file changed, 4 insertions(+), 4 deletions(-) > >>>> > >>>> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c > >>>> index 43ea0bb..c1d1dc6 100644 > >>>> --- a/drivers/mmc/mmc.c > >>>> +++ b/drivers/mmc/mmc.c > >>>> @@ -1176,10 +1176,10 @@ static int mmc_startup(struct mmc *mmc) > >>>> * ext_csd's capacity is valid if the value is more > >>>> * than 2GB > >>>> */ > >>>> - capacity = ext_csd[EXT_CSD_SEC_CNT] << 0 > >>>> - | ext_csd[EXT_CSD_SEC_CNT + 1] << 8 > >>>> - | ext_csd[EXT_CSD_SEC_CNT + 2] << 16 > >>>> - | ext_csd[EXT_CSD_SEC_CNT + 3] << 24; > >>>> + capacity = ((u64)ext_csd[EXT_CSD_SEC_CNT]) << 0 > >>>> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 1]) << 8 > >>>> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 2]) << 16 > >>>> + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 3]) << 24; > >>>> capacity *= MMC_MAX_BLOCK_LEN; > >>>> if ((capacity >> 20) > 2 * 1024) > >>>> mmc->capacity_user = capacity; > >>> > >>> Can't we just move capacity down to a u8 instead? Thanks! > >> > >> Maybe not to move down to a u8..because it's displayed the real capacity for storage. > > > > We could update those lines too? It's just that one case right there, > > yes? > > If it's possible to calculate the correct capacity? ... I think? I hadn't had my coffee yet when I did a quick compile test this morning but it looks like all of the uses of capacity would fit into a u8. Someone should check and make a formal patch :)
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index 43ea0bb..c1d1dc6 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -1176,10 +1176,10 @@ static int mmc_startup(struct mmc *mmc) * ext_csd's capacity is valid if the value is more * than 2GB */ - capacity = ext_csd[EXT_CSD_SEC_CNT] << 0 - | ext_csd[EXT_CSD_SEC_CNT + 1] << 8 - | ext_csd[EXT_CSD_SEC_CNT + 2] << 16 - | ext_csd[EXT_CSD_SEC_CNT + 3] << 24; + capacity = ((u64)ext_csd[EXT_CSD_SEC_CNT]) << 0 + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 1]) << 8 + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 2]) << 16 + | ((u64)ext_csd[EXT_CSD_SEC_CNT + 3]) << 24; capacity *= MMC_MAX_BLOCK_LEN; if ((capacity >> 20) > 2 * 1024) mmc->capacity_user = capacity;
Suspicious implicit sign extension exist. ext_csd[] is defined as "u8", capacity is defined as u64, so u8 is promoted to signed int first int the "|" expersion, then the sign extended to u64. if the tmp sign value is largeer than 0x7fffffff, after the sign extension, the upper bits of the result will all be 1. Thanks to coverity <http://www.coverity.com> e.g. u8 data_8; u64 data_64; data_8 = 0x80; data_64 = data_8 << 24; //0xffffffff80000000 data_64 = ((u64)data_8) << 24; //0x80000000 Signed-off-by: Haibo Chen <haibo.chen@nxp.com> --- drivers/mmc/mmc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)