2021-04-14 13:11:40

by Chen Jun

Subject: [PATCH v2] time: Fix overwrite err unexpected in clock_adjtime32

the correct error is covered by put_old_timex32.

Fixes: 3a4d44b61625 ("ntp: Move adjtimex related compat syscalls to native counterparts")
Signed-off-by: Chen Jun <[email protected]>
---

v2: Make "Fixes" tag correct

kernel/time/posix-timers.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index bf540f5a..dd5697d 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;
}
--
2.9.4

2021-04-15 00:32:52

by Richard Cochran

Subject: Re: [PATCH v2] time: Fix overwrite err unexpected in clock_adjtime32

On Wed, Apr 14, 2021 at 03:04:49AM +0000, Chen Jun wrote:
> the correct error is covered by put_old_timex32.
>
> Fixes: 3a4d44b61625 ("ntp: Move adjtimex related compat syscalls to native counterparts")
> Signed-off-by: Chen Jun <[email protected]>

Reviewed-by: Richard Cochran <[email protected]>

2021-04-17 12:59:28

by tip-bot2 for Jacob Pan

Subject: [tip: timers/core] posix-timers: Preserve return value in clock_adjtime32()

The following commit has been merged into the timers/core branch of tip:

Commit-ID: 2d036dfa5f10df9782f5278fc591d79d283c1fad
Gitweb: https://git.kernel.org/tip/2d036dfa5f10df9782f5278fc591d79d283c1fad
Author: Chen Jun <[email protected]>
AuthorDate: Wed, 14 Apr 2021 03:04:49
Committer: Thomas Gleixner <[email protected]>
CommitterDate: Sat, 17 Apr 2021 14:55:06 +02:00

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 <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Richard Cochran <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
---
kernel/time/posix-timers.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index bf540f5..dd5697d 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;
}