6.12-stable review patch. If anyone has any objections, please let me know.
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From: Dmitry Torokhov dmitry.torokhov@gmail.com
[ Upstream commit ae9b956cb26c0fd5a365629f2d723ab2fb14df79 ]
snto32() does exactly what sign_extend32() does, but handles potentially malformed data coming from the device. Keep the checks, but then call sign_extend32() to perform the actual conversion.
Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Link: https://patch.msgid.link/20241003144656.3786064-1-dmitry.torokhov@gmail.com Signed-off-by: Benjamin Tissoires bentiss@kernel.org Stable-dep-of: a6b87bfc2ab5 ("HID: core: Harden s32ton() against conversion to 0 bits") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hid/hid-core.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-)
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index c2783d04c6e05..1a8e88624acfb 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1318,9 +1318,7 @@ int hid_open_report(struct hid_device *device) EXPORT_SYMBOL_GPL(hid_open_report);
/* - * Convert a signed n-bit integer to signed 32-bit integer. Common - * cases are done through the compiler, the screwed things has to be - * done by hand. + * Convert a signed n-bit integer to signed 32-bit integer. */
static s32 snto32(__u32 value, unsigned n) @@ -1331,12 +1329,7 @@ static s32 snto32(__u32 value, unsigned n) if (n > 32) n = 32;
- switch (n) { - case 8: return ((__s8)value); - case 16: return ((__s16)value); - case 32: return ((__s32)value); - } - return value & (1 << (n - 1)) ? value | (~0U << n) : value; + return sign_extend32(value, n - 1); }
s32 hid_snto32(__u32 value, unsigned n)