On Wed, 12 Nov 2025 15:12:34 +0100 Quentin Schulz <[email protected]> wrote:
> Hi Köry, > > On 11/12/25 2:07 PM, Kory Maincent wrote: > > From: "Kory Maincent (TI.com)" <[email protected]> > > > > Add a null check for extension_list before calling alist_get_ptr() to > > prevent a potential null pointer dereference. If extension_get_list() > > returns NULL, alist_get_ptr() would attempt to dereference it, leading > > to undefined behavior. > > > > The fix ensures both extension_list and its first element are checked > > before proceeding with the list operation. > > > > Closes: https://lists.denx.de/pipermail/u-boot/2025-November/602892.html > > Fixes: 2d12958ee71b ("boot: Remove legacy extension board support") > > Signed-off-by: Kory Maincent (TI.com) <[email protected]> > > --- > > cmd/extension_board.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/cmd/extension_board.c b/cmd/extension_board.c > > index 86e4795ba8a..1b92be82611 100644 > > --- a/cmd/extension_board.c > > +++ b/cmd/extension_board.c > > @@ -99,7 +99,7 @@ static int do_extension_list(struct cmd_tbl *cmdtp, int > > flag, int i = 0; > > > > extension_list = extension_get_list(); > > - if (!alist_get_ptr(extension_list, 0)) { > > + if (!extension_list || !alist_get_ptr(extension_list, 0)) { > > Is it possible that one runs extension scan which returns no supported > extension (alist_empty(), the default state before calling the scan() > ops for the extension uclass driver)? Yes, we can have no extension plugged, therefore the scan won't find any extension. i.e. empty list. > In which case, we should only check whether extension_list is NULL and > not whether there's at least one extension? extension_list being NULL mean that there is no support for board specific extension driver. Maybe we could have another error message for that case. "Extension not supported" > Or at least have a different error code between "scan wasn't run" and > "scan returned no extension", if that is a distinction we can make? We could plug or unplug an extension. So it could change over time. I wrote it similarly to mmc rescan command. Regards, -- Köry Maincent, Bootlin Embedded Linux and kernel engineering https://bootlin.com
