From: Ian Abbott Date: Thu, 16 Sep 2021 14:50:23 +0000 (+0100) Subject: comedi: Fix memory leak in compat_insnlist() X-Git-Tag: v5.10.79~609 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8d6a21e4cd6a319b0662cbe4ad6199e276ac776a;p=platform%2Fkernel%2Flinux-rpi.git comedi: Fix memory leak in compat_insnlist() commit bb509a6ffed2c8b0950f637ab5779aa818ed1596 upstream. `compat_insnlist()` handles the 32-bit version of the `COMEDI_INSNLIST` ioctl (whenwhen `CONFIG_COMPAT` is enabled). It allocates memory to temporarily hold an array of `struct comedi_insn` converted from the 32-bit version in user space. This memory is only being freed if there is a fault while filling the array, otherwise it is leaked. Add a call to `kfree()` to fix the leak. Fixes: b8d47d881305 ("comedi: get rid of compat_alloc_user_space() mess in COMEDI_INSNLIST compat") Cc: Al Viro Cc: Greg Kroah-Hartman Cc: linux-staging@lists.linux.dev Cc: # 5.13+ Signed-off-by: Ian Abbott Link: https://lore.kernel.org/r/20210916145023.157479-1-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index 80d74cc..9858fae 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -3090,6 +3090,7 @@ static int compat_insnlist(struct file *file, unsigned long arg) mutex_lock(&dev->mutex); rc = do_insnlist_ioctl(dev, insns, insnlist32.n_insns, file); mutex_unlock(&dev->mutex); + kfree(insns); return rc; }