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| author | Dan Carpenter <dan.carpenter@oracle.com> | 2021-02-17 23:21:10 +0300 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2021-02-19 22:02:16 +0300 |
| commit | 182d679b2298d62bf42bb14b12a8067b8e17b617 (patch) | |
| tree | 30f4dd514f60efc32de464610152f11b75e92354 /drivers/input | |
| parent | 0958351e93fa0ac142f6dd8bd844441594f30a57 (diff) | |
| download | linux-182d679b2298d62bf42bb14b12a8067b8e17b617.tar.xz | |
Input: joydev - prevent potential read overflow in ioctl
The problem here is that "len" might be less than "joydev->nabs" so the
loops which verfy abspam[i] and keypam[] might read beyond the buffer.
Fixes: 999b874f4aa3 ("Input: joydev - validate axis/button maps before clobbering current ones")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YCyzR8WvFRw4HWw6@mwanda
[dtor: additional check for len being even in joydev_handle_JSIOCSBTNMAP]
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/input')
| -rw-r--r-- | drivers/input/joydev.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/input/joydev.c b/drivers/input/joydev.c index a2b5fbba2d3b..430dc6975004 100644 --- a/drivers/input/joydev.c +++ b/drivers/input/joydev.c @@ -456,7 +456,7 @@ static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev, if (IS_ERR(abspam)) return PTR_ERR(abspam); - for (i = 0; i < joydev->nabs; i++) { + for (i = 0; i < len && i < joydev->nabs; i++) { if (abspam[i] > ABS_MAX) { retval = -EINVAL; goto out; @@ -480,6 +480,9 @@ static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev, int i; int retval = 0; + if (len % sizeof(*keypam)) + return -EINVAL; + len = min(len, sizeof(joydev->keypam)); /* Validate the map. */ @@ -487,7 +490,7 @@ static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev, if (IS_ERR(keypam)) return PTR_ERR(keypam); - for (i = 0; i < joydev->nkey; i++) { + for (i = 0; i < (len / 2) && i < joydev->nkey; i++) { if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) { retval = -EINVAL; goto out; |