| Message ID | 20210517115907.52503-3-mika.westerberg@linux.intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | thunderbolt: NVM fixes and consolidation | expand |
On Mon, May 17, 2021 at 02:59:05PM +0300, Mika Westerberg wrote: > From: Mathias Nyman <mathias.nyman@linux.intel.com> > > Up to 64 bytes of data can be read from NVM in one go. > Read address must be dword aligned. Data is read into a local buffer. > > If caller asks to read data starting at an unaligned address then full > dword is anyway read from NVM into a local buffer. Data is then copied > from the local buffer starting at the unaligned offset to the caller > buffer. > > In cases where asked data length + unaligned offset is over 64 bytes > we need to make sure we don't read past the 64 bytes in the local > buffer when copying to caller buffer, and make sure that we don't > skip copying unaligned offset bytes from local buffer anymore after > the first round of 64 byte NVM data read. > > Fixes: b04079837b20 ("thunderbolt: Add initial support for USB4") > Cc: stable@vger.kernel.org > Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Applied to thunderbolt.git/fixes.
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c index 680bc738dd66..671d72af8ba1 100644 --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -68,15 +68,15 @@ static int usb4_do_read_data(u16 address, void *buf, size_t size, unsigned int retries = USB4_DATA_RETRIES; unsigned int offset; - offset = address & 3; - address = address & ~3; - do { - size_t nbytes = min_t(size_t, size, USB4_DATA_DWORDS * 4); unsigned int dwaddress, dwords; u8 data[USB4_DATA_DWORDS * 4]; + size_t nbytes; int ret; + offset = address & 3; + nbytes = min_t(size_t, size + offset, USB4_DATA_DWORDS * 4); + dwaddress = address / 4; dwords = ALIGN(nbytes, 4) / 4; @@ -87,6 +87,7 @@ static int usb4_do_read_data(u16 address, void *buf, size_t size, return ret; } + nbytes -= offset; memcpy(buf, data + offset, nbytes); size -= nbytes;