This is a note to let you know that I've just added the patch titled comedi: Fix memory leak in compat_insnlist() to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: comedi-fix-memory-leak-in-compat_insnlist.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From bb509a6ffed2c8b0950f637ab5779aa818ed1596 Mon Sep 17 00:00:00 2001 From: Ian Abbott <abbotti@xxxxxxxxx> Date: Thu, 16 Sep 2021 15:50:23 +0100 Subject: comedi: Fix memory leak in compat_insnlist() From: Ian Abbott <abbotti@xxxxxxxxx> 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 <viro@xxxxxxxxxxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: linux-staging@xxxxxxxxxxxxxxx Cc: <stable@xxxxxxxxxxxxxxx> # 5.13+ Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx> Link: https://lore.kernel.org/r/20210916145023.157479-1-abbotti@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/comedi/comedi_fops.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -3090,6 +3090,7 @@ static int compat_insnlist(struct file * mutex_lock(&dev->mutex); rc = do_insnlist_ioctl(dev, insns, insnlist32.n_insns, file); mutex_unlock(&dev->mutex); + kfree(insns); return rc; } Patches currently in stable-queue which might be from abbotti@xxxxxxxxx are queue-5.10/comedi-fix-memory-leak-in-compat_insnlist.patch