Re: [PATCH 1/2] mtd: spi-nor: Fix shift-out-of-bounds

["Stein, Alexander" <Alexander.Stein@tq-group.com>]

Hi Tudor,

Am Mittwoch, 16. März 2022, 08:47:40 CET schrieb Tudor.Ambarus@microchip.com:
> On 3/16/22 09:39, Alexander Stein wrote:
> 
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> > Hello,
> 
> 
> hi,
> 
> 
> > 
> > Am Samstag, 6. November 2021, 08:56:15 CET schrieb Tudor Ambarus:
> > 
> >> When paring SFDP we may choose to mask out an erase type, passing
> >> an erase size of zero to spi_nor_set_erase_type().
> >> Fix shift-out-of-bounds and just clear the erase params when
> >> passing zero for erase size.
> >> While here avoid a superfluous dereference and use 'size' directly.
> >>
> >>
> >>
> >> UBSAN: shift-out-of-bounds in drivers/mtd/spi-nor/core.c:2237:24
> >> shift exponent 4294967295 is too large for 32-bit type 'int'
> >>
> >>
> >>
> >> Fixes: 5390a8df769e ("mtd: spi-nor: add support to non-uniform SFDP SPI
> >> NOR
 flash memories") Reported-by: Alexander Stein
> >> <Alexander.Stein@tq-group.com>
> >> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> >> ---
> >> 
> >>  drivers/mtd/spi-nor/core.c | 9 +++++++--
> >>  1 file changed, 7 insertions(+), 2 deletions(-)
> >>
> >>
> >>
> >> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> >> index 3d97c189c332..a1b5d5432f41 100644
> >> --- a/drivers/mtd/spi-nor/core.c
> >> +++ b/drivers/mtd/spi-nor/core.c
> >> @@ -2230,8 +2230,13 @@ void spi_nor_set_erase_type(struct
> >> spi_nor_erase_type
 *erase, u32 size, erase->size = size;
> >> 
> >>       erase->opcode = opcode;
> >>       /* JEDEC JESD216B Standard imposes erase sizes to be power of 2.
> >>       */
> >> 
> >> -     erase->size_shift = ffs(erase->size) - 1;
> >> -     erase->size_mask = (1 << erase->size_shift) - 1;
> >> +     if (size) {
> >> +             erase->size_shift = ffs(size) - 1;
> >> +             erase->size_mask = (1 << erase->size_shift) - 1;
> >> +     } else {
> >> +             erase->size_shift = 0;
> >> +             erase->size_mask = 0;
> >> +     }
> >> 
> >>  }
> >>
> >>
> >>
> >>  /**
> > 
> > 
> > What is the status of this patch? It is not applied up until now, no? Has
> > it
 been superseeded?
> > 
> 
> 
> I think it's marked with "changes requested". I'm going to send a v2.

Is there a v2 somewhere?

Best regards,
Alexander

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