msgctl02 / msgctl04 broken for mainline 4.18rc5 / Ubuntu 4.4 & 4.15

[Cypresslin]

These two tests report that

msgctl02:

tst_safe_sysv_ipc.c:51: BROK: msgctl02.c:68: msgget(1627521041, 7b0) failed: EEXIST

msgctl04:

tst_safe_sysv_ipc.c:51: BROK: msgctl04.c:93: msgget(1627521048, 600) failed: EEXIST

This can be reproduced in both Ubuntu Xenial (4.4.0-130), Bionic (4.15.0-28), and mainline v4.18-rc5

One interesting thing is that if you run only the msgctl02 test after a reboot, it will pass for the first run:

msgctl02.c:47: PASS: msgctl(IPC_SET) msg_qbytes - 1
msgctl02.c:54: PASS: msg_qbytes = 16383

For msgctl04 only after a reboot, it will pass no matter how you beat it:

incrementing stop
tst_test.c:1015: INFO: Timeout per run is 0h 05m 00s
msgctl04.c:72: PASS: msgctl(458754, 2, 0x55d59a243980): EACCES
msgctl04.c:72: PASS: msgctl(491523, 2, 0xffffffffffffffff): EFAULT
msgctl04.c:72: PASS: msgctl(491523, 1, 0xffffffffffffffff): EFAULT
msgctl04.c:72: PASS: msgctl(491523, -1, 0x55d59a243980): EINVAL
msgctl04.c:72: PASS: msgctl(-1, 2, 0x55d59a243980): EINVAL
msgctl04.c:72: PASS: msgctl(-1, 1, 0x55d59a243980): EINVAL
msgctl04.c:72: PASS: msgctl(425985, 0, (nil)): EPERM

After msgctl04 has passed, msgctl02 can pass with multiple times without any problem.

[jstancek]

Thanks for report. The problem seems to be that test cleanup() checks for positive value, while it should be checking for nonnegative value.

According to man pages:

If successful, the return value will be the message queue identifier (a nonnegative integer), otherwise -1 with errno indicating the error.

Looking at strace, we indeed get a zero, if I run msgctl02 right after boot:

msgget(0x6100a7cf, IPC_CREAT|IPC_EXCL|0660) = 0

I'll check all msgctl tests.

[jstancek]

Should be fixed by 3e8498a
Closing.