mirror of
https://github.com/torvalds/linux.git
synced 2026-09-14 16:10:02 +02:00
777dbc9914
The max_period bound in net_timer_enable_perout() was computed as:
max_period = (u64)NETC_TMR_DEFAULT_FIPER + integral_period;
which exceeds U32_MAX when integral_period > 0 (e.g. 0x100000002 for
the default 333333333 Hz clock). A period_ns that passes this check but
exceeds U32_MAX is then silently truncated when stored into the u32
struct netc_pp::period field.
A truncated value of zero can reach netc_timer_set_perout_alarm(), where
the local u32 period variable would also be 0, causing a divide-by-zero
in roundup_u64(delta, period) whenever the stime < min_time branch is
taken (which always happens for a start time of {0, 0}).
Additionally, netc_timer_enable_periodic_pulse() and
netc_timer_enable_fiper() both compute:
fiper = pp->period - integral_period;
A zero pp->period results in an unsigned wraparound to 0xFFFFFFFD,
mis-programming the FIPER hardware register.
Fix all three issues by capping max_period at NETC_TMR_DEFAULT_FIPER
(0xFFFFFFFF). This ensures that any period_ns passing the range check
fits in a u32 without truncation, so the stored value is always valid
and non-zero. The accepted range is reduced by integral_period ns
(typically only a few nanoseconds), which is negligible in practice.
Fixes:
|
||
|---|---|---|
| .. | ||
| Kconfig | ||
| Makefile | ||
| ptp_chardev.c | ||
| ptp_clock.c | ||
| ptp_clockmatrix.c | ||
| ptp_clockmatrix.h | ||
| ptp_dfl_tod.c | ||
| ptp_dte.c | ||
| ptp_fc3.c | ||
| ptp_fc3.h | ||
| ptp_idt82p33.c | ||
| ptp_idt82p33.h | ||
| ptp_ines.c | ||
| ptp_kvm_arm.c | ||
| ptp_kvm_common.c | ||
| ptp_kvm_x86.c | ||
| ptp_mock.c | ||
| ptp_netc.c | ||
| ptp_ocp.c | ||
| ptp_pch.c | ||
| ptp_private.h | ||
| ptp_qoriq.c | ||
| ptp_s390.c | ||
| ptp_sysfs.c | ||
| ptp_vclock.c | ||
| ptp_vmclock.c | ||
| ptp_vmw.c | ||