From b6c8dafc9d86eb77e502bb018ec4105e8d2fbf78 Mon Sep 17 00:00:00 2001 From: Samuel Thibault Date: Sun, 4 Feb 2024 16:57:36 +0100 Subject: [PATCH] speakup: Fix 8bit characters from direct synth When userland echoes 8bit characters to /dev/synth with e.g. echo -e '\xe9' > /dev/synth synth_write would get characters beyond 0x7f, and thus negative when char is signed. When given to synth_buffer_add which takes a u16, this would sign-extend and produce a U+ffxy character rather than U+xy. Users thus get garbled text instead of accents in their output. Let's fix this by making sure that we read unsigned characters. Signed-off-by: Samuel Thibault Fixes: 89fc2ae80bb1 ("speakup: extend synth buffer to 16bit unicode characters") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240204155736.2oh4ot7tiaa2wpbh@begin Signed-off-by: Greg Kroah-Hartman --- drivers/accessibility/speakup/synth.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/accessibility/speakup/synth.c b/drivers/accessibility/speakup/synth.c index eea2a2fa4f01..45f906103133 100644 --- a/drivers/accessibility/speakup/synth.c +++ b/drivers/accessibility/speakup/synth.c @@ -208,8 +208,10 @@ void spk_do_flush(void) wake_up_process(speakup_task); } -void synth_write(const char *buf, size_t count) +void synth_write(const char *_buf, size_t count) { + const unsigned char *buf = (const unsigned char *) _buf; + while (count--) synth_buffer_add(*buf++); synth_start();