On Thu, Sep 12, 2024 at 12:30:42PM -0500, Brandon Nielsen wrote: > On 9/12/24 3:39 AM, Stanislaw Gruszka wrote: > > On Thu, Sep 12, 2024 at 01:01:21AM +0200, Ben Hutchings wrote: > > > iwlegacy uses command buffers with a payload size of 320 > > > bytes (default) or 4092 bytes (huge). The struct il_device_cmd type > > > describes the default buffers and there is no separate type describing > > > the huge buffers. > > > > > > The il_enqueue_hcmd() function works with both default and huge > > > buffers, and has a memcpy() to the buffer payload. The size of > > > this copy may exceed 320 bytes when using a huge buffer, which > > > now results in a run-time warning: > > > > > > memcpy: detected field-spanning write (size 1014) of single field "&out_cmd->cmd.payload" at drivers/net/wireless/intel/iwlegacy/common.c:3170 (size 320) > > > > > > To fix this: > > > > > > - Define a new struct type for huge buffers, with a correctly sized > > > payload field > > > - When using a huge buffer in il_enqueue_hcmd(), cast the command > > > buffer pointer to that type when looking up the payload field > > > > > > Reported-by: Martin-Éric Racine <martin-eric.racine@xxxxxx> > > > References: https://bugs.debian.org/1062421 > > > References: https://bugzilla.kernel.org/show_bug.cgi?id=219124 > > > Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> > > > Fixes: 54d9469bc515 ("fortify: Add run-time WARN for cross-field memcpy()") > > > Tested-by: Martin-Éric Racine <martin-eric.racine@xxxxxx> > > > Tested-by: Brandon Nielsen <nielsenb@xxxxxxxxxxx> > > > > I proposed diffrent fix for this here: > > https://lore.kernel.org/linux-wireless/20240520073210.GA693073@xxxxx/ > > but never get feedback if it works on real HW. > > So I prefer this one, sice it was tested. > > > > Acked-by: Stanislaw Gruszka <stf_xl@xxxxx> > > > > Martin-Éric and Brandon, could you plase also test patch from > > https://lore.kernel.org/linux-wireless/Zr2gxERA3RL3EwRe@elsanto/ > > if it does not break the driver? > > > > As far as I can tell nothing breaks with that additional patch applied. Great, thanks for testing the patch. Stanislaw
