Hello!
This is an experimental semi-automated report about issues detected by
Coverity from a scan of next-20221202 as part of the linux-next scan project:
https://scan.coverity.com/projects/linux-next-weekly-scan
You're getting this email because you were associated with the identified
lines of code (noted below) that were touched by commits:
Thu Feb 3 13:57:56 2022 +0100
417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for mt7916")
Coverity reported the following:
*** CID 1527801: Memory - illegal accesses (OVERRUN)
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:3005 in mt7915_mcu_get_chan_mib_info()
2999 start = 5;
3000 ofs = 0;
3001 }
3002
3003 for (i = 0; i < 5; i++) {
3004 req[i].band = cpu_to_le32(phy->mt76->band_idx);
vvv CID 1527801: Memory - illegal accesses (OVERRUN)
vvv Overrunning array "offs" of 9 4-byte elements at element index 9 (byte offset 39) using index "i + start" (which evaluates to 9).
3005 req[i].offs = cpu_to_le32(offs[i + start]);
3006
3007 if (!is_mt7915(&dev->mt76) && i == 3)
3008 break;
3009 }
3010
If this is a false positive, please let us know so we can mark it as
such, or teach the Coverity rules to be smarter. If not, please make
sure fixes get into linux-next. :) For patches fixing this, please
include these lines (but double-check the "Fixes" first):
Reported-by: coverity-bot <[email protected]>
Addresses-Coverity-ID: 1527801 ("Memory - illegal accesses")
Fixes: 417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for mt7916")
Thanks for your attention!
--
Coverity-bot
On Fri, 2022-12-02 at 14:24 -0800, coverity-bot wrote:
> Hello!
>
> This is an experimental semi-automated report about issues detected
> by
> Coverity from a scan of next-20221202 as part of the linux-next scan
> project:
>
https://urldefense.com/v3/__https://scan.coverity.com/projects/linux-next-weekly-scan__;!!CTRNKA9wMg0ARbw!j7j_C0KpO4VD2yMOodvpeIexTGq4fhy2yq6nokNua9u4LToiUOLk4ou8JFFNrXkrh80d5BK2k44faRQstHE9$
>
>
> You're getting this email because you were associated with the
> identified
> lines of code (noted below) that were touched by commits:
>
> Thu Feb 3 13:57:56 2022 +0100
> 417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for
> mt7916")
>
> Coverity reported the following:
>
> *** CID 1527801: Memory - illegal accesses (OVERRUN)
> drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:3005 in
> mt7915_mcu_get_chan_mib_info()
> 2999 start = 5;
> 3000 ofs = 0;
> 3001 }
> 3002
> 3003 for (i = 0; i < 5; i++) {
> 3004 req[i].band = cpu_to_le32(phy->mt76->band_idx);
> vvv CID 1527801: Memory - illegal accesses (OVERRUN)
> vvv Overrunning array "offs" of 9 4-byte elements at element
> index 9 (byte offset 39) using index "i + start" (which evaluates to
> 9).
> 3005 req[i].offs = cpu_to_le32(offs[i + start]);
> 3006
> 3007 if (!is_mt7915(&dev->mt76) && i == 3)
> 3008 break;
> 3009 }
> 3010
>
> If this is a false positive, please let us know so we can mark it as
> such, or teach the Coverity rules to be smarter. If not, please make
> sure fixes get into linux-next. :) For patches fixing this, please
> include these lines (but double-check the "Fixes" first):
>
I think this is a false postive as the subsequent check 'if
(!is_mt7915(&dev->mt76) && i == 3)' should break array "offs" of 8.
Ryder
> Reported-by: coverity-bot <[email protected]>
> Addresses-Coverity-ID: 1527801 ("Memory - illegal accesses")
> Fixes: 417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for
> mt7916")
>
> Thanks for your attention!
>
On Fri, Dec 02, 2022 at 10:56:19PM +0000, Ryder Lee wrote:
> On Fri, 2022-12-02 at 14:24 -0800, coverity-bot wrote:
> > Hello!
> >
> > This is an experimental semi-automated report about issues detected
> > by
> > Coverity from a scan of next-20221202 as part of the linux-next scan
> > project:
> >
> https://urldefense.com/v3/__https://scan.coverity.com/projects/linux-next-weekly-scan__;!!CTRNKA9wMg0ARbw!j7j_C0KpO4VD2yMOodvpeIexTGq4fhy2yq6nokNua9u4LToiUOLk4ou8JFFNrXkrh80d5BK2k44faRQstHE9$?
> >
> >
> > You're getting this email because you were associated with the
> > identified
> > lines of code (noted below) that were touched by commits:
> >
> > Thu Feb 3 13:57:56 2022 +0100
> > 417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for
> > mt7916")
> >
> > Coverity reported the following:
> >
> > *** CID 1527801: Memory - illegal accesses (OVERRUN)
> > drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:3005 in
> > mt7915_mcu_get_chan_mib_info()
> > 2999 start = 5;
> > 3000 ofs = 0;
> > 3001 }
> > 3002
> > 3003 for (i = 0; i < 5; i++) {
> > 3004 req[i].band = cpu_to_le32(phy->mt76->band_idx);
> > vvv CID 1527801: Memory - illegal accesses (OVERRUN)
> > vvv Overrunning array "offs" of 9 4-byte elements at element
> > index 9 (byte offset 39) using index "i + start" (which evaluates to
> > 9).
> > 3005 req[i].offs = cpu_to_le32(offs[i + start]);
> > 3006
> > 3007 if (!is_mt7915(&dev->mt76) && i == 3)
> > 3008 break;
> > 3009 }
> > 3010
> >
> > If this is a false positive, please let us know so we can mark it as
> > such, or teach the Coverity rules to be smarter. If not, please make
> > sure fixes get into linux-next. :) For patches fixing this, please
> > include these lines (but double-check the "Fixes" first):
> >
>
> I think this is a false postive as the subsequent check 'if
> (!is_mt7915(&dev->mt76) && i == 3)' should break array "offs" of 8.
Ah, okay. What if is_mt7915(&dev->mt76) is always true?
-Kees
>
> Ryder
>
> > Reported-by: coverity-bot <[email protected]>
> > Addresses-Coverity-ID: 1527801 ("Memory - illegal accesses")
> > Fixes: 417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for
> > mt7916")
> >
> > Thanks for your attention!
> >
--
Kees Cook
On Fri, 2022-12-02 at 15:04 -0800, Kees Cook wrote:
> >
> On Fri, Dec 02, 2022 at 10:56:19PM +0000, Ryder Lee wrote:
> > On Fri, 2022-12-02 at 14:24 -0800, coverity-bot wrote:
> > > Hello!
> > >
> > > This is an experimental semi-automated report about issues
> > > detected
> > > by
> > > Coverity from a scan of next-20221202 as part of the linux-next
> > > scan
> > > project:
> > >
> >
> >
https://urldefense.com/v3/__https://scan.coverity.com/projects/linux-next-weekly-scan__;!!CTRNKA9wMg0ARbw!j7j_C0KpO4VD2yMOodvpeIexTGq4fhy2yq6nokNua9u4LToiUOLk4ou8JFFNrXkrh80d5BK2k44faRQstHE9$
> >
> > >
> > >
> > > You're getting this email because you were associated with the
> > > identified
> > > lines of code (noted below) that were touched by commits:
> > >
> > > Thu Feb 3 13:57:56 2022 +0100
> > > 417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for
> > > mt7916")
> > >
> > > Coverity reported the following:
> > >
> > > *** CID 1527801: Memory - illegal accesses (OVERRUN)
> > > drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:3005 in
> > > mt7915_mcu_get_chan_mib_info()
> > > 2999 start = 5;
> > > 3000 ofs = 0;
> > > 3001 }
> > > 3002
> > > 3003 for (i = 0; i < 5; i++) {
> > > 3004 req[i].band = cpu_to_le32(phy->mt76->band_idx);
> > > vvv CID 1527801: Memory - illegal accesses (OVERRUN)
> > > vvv Overrunning array "offs" of 9 4-byte elements at element
> > > index 9 (byte offset 39) using index "i + start" (which evaluates
> > > to
> > > 9).
> > > 3005 req[i].offs = cpu_to_le32(offs[i + start]);
> > > 3006
> > > 3007 if (!is_mt7915(&dev->mt76) && i == 3)
> > > 3008 break;
> > > 3009 }
> > > 3010
> > >
> > > If this is a false positive, please let us know so we can mark it
> > > as
> > > such, or teach the Coverity rules to be smarter. If not, please
> > > make
> > > sure fixes get into linux-next. :) For patches fixing this,
> > > please
> > > include these lines (but double-check the "Fixes" first):
> > >
> >
> > I think this is a false postive as the subsequent check 'if
> > (!is_mt7915(&dev->mt76) && i == 3)' should break array "offs" of 8.
>
> Ah, okay. What if is_mt7915(&dev->mt76) is always true?
>
> -Kees
int start = 0;
if (!is_mt7915(&dev->mt76)) {
start = 5;
ofs = 0;
}
for (i = 0; i < 5; i++) {
req[i].band = cpu_to_le32(phy->band_idx);
req[i].offs = cpu_to_le32(offs[i + start]);
if (!is_mt7915(&dev->mt76) && i == 3) //
break;
}
For 'is_mt7915' case, start:0 and i: 0 1 2 3 4, whereas !is_mt7915'
case, start:5 and i: 0 1 2 3 (then break).
I know it's a bit tricky. This is used to differentiate chipset
revision.
Ryder
On Fri, Dec 02, 2022 at 11:42:36PM +0000, Ryder Lee wrote:
> On Fri, 2022-12-02 at 15:04 -0800, Kees Cook wrote:
> > >
> > On Fri, Dec 02, 2022 at 10:56:19PM +0000, Ryder Lee wrote:
> > > On Fri, 2022-12-02 at 14:24 -0800, coverity-bot wrote:
> > > > Hello!
> > > >
> > > > This is an experimental semi-automated report about issues
> > > > detected
> > > > by
> > > > Coverity from a scan of next-20221202 as part of the linux-next
> > > > scan
> > > > project:
> > > >
> > >
> > >
> https://urldefense.com/v3/__https://scan.coverity.com/projects/linux-next-weekly-scan__;!!CTRNKA9wMg0ARbw!j7j_C0KpO4VD2yMOodvpeIexTGq4fhy2yq6nokNua9u4LToiUOLk4ou8JFFNrXkrh80d5BK2k44faRQstHE9$
> > >
> > > >
> > > >
> > > > You're getting this email because you were associated with the
> > > > identified
> > > > lines of code (noted below) that were touched by commits:
> > > >
> > > > Thu Feb 3 13:57:56 2022 +0100
> > > > 417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for
> > > > mt7916")
> > > >
> > > > Coverity reported the following:
> > > >
> > > > *** CID 1527801: Memory - illegal accesses (OVERRUN)
> > > > drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:3005 in
> > > > mt7915_mcu_get_chan_mib_info()
> > > > 2999 start = 5;
> > > > 3000 ofs = 0;
> > > > 3001 }
> > > > 3002
> > > > 3003 for (i = 0; i < 5; i++) {
> > > > 3004 req[i].band = cpu_to_le32(phy->mt76->band_idx);
> > > > vvv CID 1527801: Memory - illegal accesses (OVERRUN)
> > > > vvv Overrunning array "offs" of 9 4-byte elements at element
> > > > index 9 (byte offset 39) using index "i + start" (which evaluates
> > > > to
> > > > 9).
> > > > 3005 req[i].offs = cpu_to_le32(offs[i + start]);
> > > > 3006
> > > > 3007 if (!is_mt7915(&dev->mt76) && i == 3)
> > > > 3008 break;
> > > > 3009 }
> > > > 3010
> > > >
> > > > If this is a false positive, please let us know so we can mark it
> > > > as
> > > > such, or teach the Coverity rules to be smarter. If not, please
> > > > make
> > > > sure fixes get into linux-next. :) For patches fixing this,
> > > > please
> > > > include these lines (but double-check the "Fixes" first):
> > > >
> > >
> > > I think this is a false postive as the subsequent check 'if
> > > (!is_mt7915(&dev->mt76) && i == 3)' should break array "offs" of 8.
> >
> > Ah, okay. What if is_mt7915(&dev->mt76) is always true?
> >
> > -Kees
>
> int start = 0;
>
> if (!is_mt7915(&dev->mt76)) {
> start = 5;
> ofs = 0;
> }
>
> for (i = 0; i < 5; i++) {
> req[i].band = cpu_to_le32(phy->band_idx);
> req[i].offs = cpu_to_le32(offs[i + start]);
>
> if (!is_mt7915(&dev->mt76) && i == 3) //
> break;
> }
>
> For 'is_mt7915' case, start:0 and i: 0 1 2 3 4, whereas !is_mt7915'
> case, start:5 and i: 0 1 2 3 (then break).
>
> I know it's a bit tricky. This is used to differentiate chipset
> revision.
Ah-ha! Gotcha now. Thanks for the details and sorry for the noise! :)
-Kees
--
Kees Cook