4.19-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 9bc30ab82108e6a34dc63bf956b49edf71b1681a ]
The x/y command parsing has been broken since commit 129957069e6a ("staging: panel: Fixed checkpatch warning about simple_strtoul()").
Commit b34050fadb86 ("auxdisplay: charlcd: Fix and clean up handling of x/y commands") fixed some problems by rewriting the parsing code, but also broke things further by removing the check for a complete command before attempting to parse it. As a result, parsing is terminated at the first x or y character.
This reinstates the check for a final semicolon. Whereas the original code use strchr(), this is wasteful seeing as the semicolon is always at the end of the buffer. Thus check this character directly instead.
Signed-off-by: Mans Rullgard mans@mansr.com Signed-off-by: Miguel Ojeda miguel.ojeda.sandonis@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/auxdisplay/charlcd.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c index 81c22d20d9d9..60e0b772673f 100644 --- a/drivers/auxdisplay/charlcd.c +++ b/drivers/auxdisplay/charlcd.c @@ -538,6 +538,9 @@ static inline int handle_lcd_special_code(struct charlcd *lcd) } case 'x': /* gotoxy : LxXXX[yYYY]; */ case 'y': /* gotoxy : LyYYY[xXXX]; */ + if (priv->esc_seq.buf[priv->esc_seq.len - 1] != ';') + break; + /* If the command is valid, move to the new address */ if (parse_xy(esc, &priv->addr.x, &priv->addr.y)) charlcd_gotoxy(lcd);