The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 2d036dfa5f10df9782f5278fc591d79d283c1fad Mon Sep 17 00:00:00 2001

From: Chen Jun chenjun102@huawei.com Date: Wed, 14 Apr 2021 03:04:49 +0000 Subject: [PATCH] posix-timers: Preserve return value in clock_adjtime32()

The return value on success (>= 0) is overwritten by the return value of put_old_timex32(). That works correct in the fault case, but is wrong for the success case where put_old_timex32() returns 0.

Just check the return value of put_old_timex32() and return -EFAULT in case it is not zero.

[ tglx: Massage changelog ]

Fixes: 3a4d44b61625 ("ntp: Move adjtimex related compat syscalls to native counterparts") Signed-off-by: Chen Jun chenjun102@huawei.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Richard Cochran richardcochran@gmail.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210414030449.90692-1-chenjun102@huawei.com

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index bf540f5a4115..dd5697d7347b 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -1191,8 +1191,8 @@ SYSCALL_DEFINE2(clock_adjtime32, clockid_t, which_clock,

err = do_clock_adjtime(which_clock, &ktx);

- if (err >= 0) - err = put_old_timex32(utp, &ktx); + if (err >= 0 && put_old_timex32(utp, &ktx)) + return -EFAULT;

return err; }