diff options
| author | Jia-Ju Bai <baijiaju1990@gmail.com> | 2018-09-01 16:25:08 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-26 08:36:36 +0200 |
| commit | 2ccd62789ef0ec1bd8efd52d9581b84331f6004d (patch) | |
| tree | 0dd591436d14ee0aa75968569db4ab6e572980fe | |
| parent | b1507f458d22fe86334ebc53b8f26de74598c37a (diff) | |
usb: misc: uss720: Fix two sleep-in-atomic-context bugs
commit bc8acc214d3f1cafebcbcd101a695bbac716595d upstream.
async_complete() in uss720.c is a completion handler function for the
USB driver. So it should not sleep, but it is can sleep according to the
function call paths (from bottom to top) in Linux-4.16.
[FUNC] set_1284_register(GFP_KERNEL)
drivers/usb/misc/uss720.c, 372:
set_1284_register in parport_uss720_frob_control
drivers/parport/ieee1284.c, 560:
[FUNC_PTR]parport_uss720_frob_control in parport_ieee1284_ack_data_avail
drivers/parport/ieee1284.c, 577:
parport_ieee1284_ack_data_avail in parport_ieee1284_interrupt
./include/linux/parport.h, 474:
parport_ieee1284_interrupt in parport_generic_irq
drivers/usb/misc/uss720.c, 116:
parport_generic_irq in async_complete
[FUNC] get_1284_register(GFP_KERNEL)
drivers/usb/misc/uss720.c, 382:
get_1284_register in parport_uss720_read_status
drivers/parport/ieee1284.c, 555:
[FUNC_PTR]parport_uss720_read_status in parport_ieee1284_ack_data_avail
drivers/parport/ieee1284.c, 577:
parport_ieee1284_ack_data_avail in parport_ieee1284_interrupt
./include/linux/parport.h, 474:
parport_ieee1284_interrupt in parport_generic_irq
drivers/usb/misc/uss720.c, 116:
parport_generic_irq in async_complete
Note that [FUNC_PTR] means a function pointer call is used.
To fix these bugs, GFP_KERNEL is replaced with GFP_ATOMIC.
These bugs are found by my static analysis tool DSAC.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/misc/uss720.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/usb/misc/uss720.c b/drivers/usb/misc/uss720.c index 9ff66525924e..e77465a30ac6 100644 --- a/drivers/usb/misc/uss720.c +++ b/drivers/usb/misc/uss720.c @@ -385,7 +385,7 @@ static unsigned char parport_uss720_frob_control(struct parport *pp, unsigned ch mask &= 0x0f; val &= 0x0f; d = (priv->reg[1] & (~mask)) ^ val; - if (set_1284_register(pp, 2, d, GFP_KERNEL)) + if (set_1284_register(pp, 2, d, GFP_ATOMIC)) return 0; priv->reg[1] = d; return d & 0xf; @@ -395,7 +395,7 @@ static unsigned char parport_uss720_read_status(struct parport *pp) { unsigned char ret; - if (get_1284_register(pp, 1, &ret, GFP_KERNEL)) + if (get_1284_register(pp, 1, &ret, GFP_ATOMIC)) return 0; return ret & 0xf8; } |