On Thu, 1 Apr 2021 14:58:23 +0900 Tetsuo Handa <penguin-ker...@i-love.sakura.ne.jp> wrote:
> KMSAN complains that new_value at cpumask_parse_user() from > write_irq_affinity() from irq_affinity_proc_write() is uninitialized. > > [ 148.133411][ T5509] ===================================================== > [ 148.135383][ T5509] BUG: KMSAN: uninit-value in find_next_bit+0x325/0x340 > [ 148.137819][ T5509] > [ 148.138448][ T5509] Local variable > ----new_value.i@irq_affinity_proc_write created at: > [ 148.140768][ T5509] irq_affinity_proc_write+0xc3/0x3d0 > [ 148.142298][ T5509] irq_affinity_proc_write+0xc3/0x3d0 > [ 148.143823][ T5509] ===================================================== > > Since bitmap_parse() from cpumask_parse_user() calls find_next_bit(), > any alloc_cpumask_var() + cpumask_parse_user() sequence has possibility > that find_next_bit() accesses uninitialized cpu mask variable. Fix this > problem by replacing alloc_cpumask_var() with zalloc_cpumask_var(). > > Signed-off-by: Tetsuo Handa <penguin-ker...@i-love.sakura.ne.jp> > --- > kernel/irq/proc.c | 4 ++-- > kernel/profile.c | 2 +- > kernel/trace/trace.c | 2 +- Acked-by: Steven Rostedt (VMware) <rost...@goodmis.org> -- Steve
