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| author |   Li RongQing <lirongqing@baidu.com> | 2018-04-10 09:16:06 +0800 |
|---|---|---|
| committer |   Thomas Gleixner <tglx@linutronix.de> | 2018-04-10 16:46:39 +0200 |
| commit | a774635db5c430cbf21fa5d2f2df3d23aaa8e782 (patch) | |
| tree | 901a79ca1293a6ef62e57de71e74496347f1ad35 /drivers/mtd/lpddr/lpddr_cmds.c | |
| parent | x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption (diff) | |
| download | wireguard-linux-a774635db5c430cbf21fa5d2f2df3d23aaa8e782.tar.xz wireguard-linux-a774635db5c430cbf21fa5d2f2df3d23aaa8e782.zip | |
x86/apic: Fix signedness bug in APIC ID validity checks
The APIC ID as parsed from ACPI MADT is validity checked with the
apic->apic_id_valid() callback, which depends on the selected APIC type.
For non X2APIC types APIC IDs >= 0xFF are invalid, but values > 0x7FFFFFFF
are detected as valid. This happens because the 'apicid' argument of the
apic_id_valid() callback is type 'int'. So the resulting comparison
apicid < 0xFF
evaluates to true for all unsigned int values > 0x7FFFFFFF which are handed
to default_apic_id_valid(). As a consequence, invalid APIC IDs in !X2APIC
mode are considered valid and accounted as possible CPUs.
Change the apicid argument type of the apic_id_valid() callback to u32 so
the evaluation is unsigned and returns the correct result.
[ tglx: Massaged changelog ]
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: jgross@suse.com
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/1523322966-10296-1-git-send-email-lirongqing@baidu.com
Diffstat (limited to '')
0 files changed, 0 insertions, 0 deletions