From 3d6cbe2361ebbb5a0037225af0cd890e666b2ec0 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Sun, 16 Sep 2012 04:18:50 +0100 Subject: [PATCH] staging: speakup_soft: Fix reading of init string commit 40fe4f89671fb3c7ded94190fb267402a38b0261 upstream. softsynth_read() reads a character at a time from the init string; when it finds the null terminator it sets the initialized flag but then repeats the last character. Additionally, if the read() buffer is not big enough for the init string, the next read() will start reading from the beginning again. So the caller may never progress to reading anything else. Replace the simple initialized flag with the current position in the init string, carried over between calls. Switch to reading real data once this reaches the null terminator. (This assumes that the length of the init string can't change, which seems to be the case. Really, the string and position belong together in a per-file private struct.) Tested-by: Samuel Thibault Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- drivers/staging/speakup/speakup_soft.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) diff --git a/drivers/staging/speakup/speakup_soft.c b/drivers/staging/speakup/speakup_soft.c index 42cdafeea35e..b5130c8bcb64 100644 --- a/drivers/staging/speakup/speakup_soft.c +++ b/drivers/staging/speakup/speakup_soft.c @@ -40,7 +40,7 @@ static int softsynth_is_alive(struct spk_synth *synth); static unsigned char get_index(void); static struct miscdevice synth_device; -static int initialized; +static int init_pos; static int misc_registered; static struct var_t vars[] = { @@ -194,7 +194,7 @@ static int softsynth_close(struct inode *inode, struct file *fp) unsigned long flags; spk_lock(flags); synth_soft.alive = 0; - initialized = 0; + init_pos = 0; spk_unlock(flags); /* Make sure we let applications go before leaving */ speakup_start_ttys(); @@ -239,13 +239,8 @@ static ssize_t softsynth_read(struct file *fp, char *buf, size_t count, ch = '\x18'; } else if (synth_buffer_empty()) { break; - } else if (!initialized) { - if (*init) { - ch = *init; - init++; - } else { - initialized = 1; - } + } else if (init[init_pos]) { + ch = init[init_pos++]; } else { ch = synth_buffer_getc(); } -- 2.39.5