Commit a8c6efee authored Mar 17, 2021 by Dean Anderson Committed by Greg Kroah-Hartman May 22, 2021

usb: gadget/function/f_fs string table fix for multiple languages



commit 55b74ce7d2ce0b0058f3e08cab185a0afacfe39e upstream.

Fixes bug with the handling of more than one language in
the string table in f_fs.c.
str_count was not reset for subsequent language codes.
str_count-- "rolls under" and processes u32 max strings on
the processing of the second language entry.
The existing bug can be reproduced by adding a second language table
to the structure "strings" in tools/usb/ffs-test.c.

Signed-off-by: Dean Anderson <dean@sensoray.com>
Link: https://lore.kernel.org/r/20210317224109.21534-1-dean@sensoray.com


Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 27876060

drivers/usb/gadget/function/f_fs.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -2553,6 +2553,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,

		do { /* lang_count > 0 so we can use do-while */
		unsigned needed = needed_count;
		u32 str_per_lang = str_count;

		if (unlikely(len < 3))
		goto error_free;
		@@ -2588,7 +2589,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,

		data += length + 1;
		len -= length + 1;
		} while (--str_count);
		} while (--str_per_lang);

		s->id = 0; /* terminator */
		s->s = NULL;