diff options
| author | Lee Jones <lee@kernel.org> | 2023-12-13 19:42:31 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-12-15 15:55:29 +0300 |
| commit | c1a371866db9c44ab3004b5fc06df066a1b96262 (patch) | |
| tree | fe877ddf22593b0282c1a467403e2824c3f76c79 | |
| parent | 0466e7e693efe6647f23532529a9c41a1fa5f4ac (diff) | |
| download | linux-c1a371866db9c44ab3004b5fc06df066a1b96262.tar.xz | |
usb: gadget: f_uac1: Replace snprintf() with the safer scnprintf() variant
There is a general misunderstanding amongst engineers that {v}snprintf()
returns the length of the data *actually* encoded into the destination
array. However, as per the C99 standard {v}snprintf() really returns
the length of the data that *would have been* written if there were
enough space for it. This misunderstanding has led to buffer-overruns
in the past. It's generally considered safer to use the {v}scnprintf()
variants in their place (or even sprintf() in simple cases). So let's
do that.
Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Cc: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Cc: Julian Scheel <julian@jusst.de>
Cc: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20231213164246.1021885-3-lee@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/gadget/function/f_uac1.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c index 78634ea7863a..7de74a3dd392 100644 --- a/drivers/usb/gadget/function/f_uac1.c +++ b/drivers/usb/gadget/function/f_uac1.c @@ -1634,7 +1634,7 @@ static ssize_t f_uac1_opts_##name##_show(struct config_item *item, \ int result; \ \ mutex_lock(&opts->lock); \ - result = snprintf(page, sizeof(opts->name), "%s", opts->name); \ + result = scnprintf(page, sizeof(opts->name), "%s", opts->name); \ mutex_unlock(&opts->lock); \ \ return result; \ @@ -1652,7 +1652,7 @@ static ssize_t f_uac1_opts_##name##_store(struct config_item *item, \ goto end; \ } \ \ - ret = snprintf(opts->name, min(sizeof(opts->name), len), \ + ret = scnprintf(opts->name, min(sizeof(opts->name), len), \ "%s", page); \ \ end: \ @@ -1758,7 +1758,7 @@ static struct usb_function_instance *f_audio_alloc_inst(void) opts->req_number = UAC1_DEF_REQ_NUM; - snprintf(opts->function_name, sizeof(opts->function_name), "AC Interface"); + scnprintf(opts->function_name, sizeof(opts->function_name), "AC Interface"); return &opts->func_inst; } |