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| author | Lee Jones <lee@kernel.org> | 2023-12-13 16:42:32 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-11-01 01:58:26 +0100 |
| commit | 3af6c72854138d241e8a80560b444dd6752481b1 (patch) | |
| tree | 1fdeac57272d6b41fe1035f547adfd6f1d72cf2c /drivers/usb | |
| parent | c691c2adeb75b3e385dff3efcaef978e08698bf8 (diff) | |
| download | linux-3af6c72854138d241e8a80560b444dd6752481b1.tar.gz linux-3af6c72854138d241e8a80560b444dd6752481b1.tar.bz2 linux-3af6c72854138d241e8a80560b444dd6752481b1.zip | |
usb: gadget: f_uac2: Replace snprintf() with the safer scnprintf() variant
[ Upstream commit 60034e0aedf507888c4a880f57011bb7f5d7700c ]
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: James Gruber <jimmyjgruber@gmail.com>
Cc: Yadwinder Singh <yadi.brar01@gmail.com>
Cc: Jaswinder Singh <jaswinder.singh@linaro.org>
Cc: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20231213164246.1021885-4-lee@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 9499327714de ("usb: gadget: f_uac2: fix return value for UAC2_ATTRIBUTE_STRING store")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/gadget/function/f_uac2.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c index 0219cd79493a..55a4f07bc9cc 100644 --- a/drivers/usb/gadget/function/f_uac2.c +++ b/drivers/usb/gadget/function/f_uac2.c @@ -2042,7 +2042,7 @@ static ssize_t f_uac2_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; \ @@ -2060,7 +2060,7 @@ static ssize_t f_uac2_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: \ @@ -2178,7 +2178,7 @@ static struct usb_function_instance *afunc_alloc_inst(void) opts->req_number = UAC2_DEF_REQ_NUM; opts->fb_max = FBACK_FAST_MAX; - snprintf(opts->function_name, sizeof(opts->function_name), "Source/Sink"); + scnprintf(opts->function_name, sizeof(opts->function_name), "Source/Sink"); return &opts->func_inst; } |