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Revert sr workarounds #47

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In order to address suspend/resume instability, clang
version is updated to 12.0.3. With clang version updated
to 12.0.3, workarounds are reverted.

Tracked-On: OAM-96701
Signed-off-by: Jeevaka Prabu Badrappan <[email protected]>
sysopenci pushed a commit that referenced this pull request May 28, 2021
[ Upstream commit d5027ca63e0e778b641cf23e3f5c6d6212cf412b ]

Ritesh reported a bug [1] against UML, noting that it crashed on
startup. The backtrace shows the following (heavily redacted):

(gdb) bt
...
 #26 0x0000000060015b5d in sem_init () at ipc/sem.c:268
 #27 0x00007f89906d92f7 in ?? () from /lib/x86_64-linux-gnu/libcom_err.so.2
 #28 0x00007f8990ab8fb2 in call_init (...) at dl-init.c:72
...
 #40 0x00007f89909bf3a6 in nss_load_library (...) at nsswitch.c:359
...
 #44 0x00007f8990895e35 in _nss_compat_getgrnam_r (...) at nss_compat/compat-grp.c:486
 #45 0x00007f8990968b85 in __getgrnam_r [...]
 #46 0x00007f89909d6b77 in grantpt [...]
 #47 0x00007f8990a9394e in __GI_openpty [...]
 #48 0x00000000604a1f65 in openpty_cb (...) at arch/um/os-Linux/sigio.c:407
 #49 0x00000000604a58d0 in start_idle_thread (...) at arch/um/os-Linux/skas/process.c:598
 #50 0x0000000060004a3d in start_uml () at arch/um/kernel/skas/process.c:45
 #51 0x00000000600047b2 in linux_main (...) at arch/um/kernel/um_arch.c:334
 #52 0x000000006000574f in main (...) at arch/um/os-Linux/main.c:144

indicating that the UML function openpty_cb() calls openpty(),
which internally calls __getgrnam_r(), which causes the nsswitch
machinery to get started.

This loads, through lots of indirection that I snipped, the
libcom_err.so.2 library, which (in an unknown function, "??")
calls sem_init().

Now, of course it wants to get libpthread's sem_init(), since
it's linked against libpthread. However, the dynamic linker
looks up that symbol against the binary first, and gets the
kernel's sem_init().

Hajime Tazaki noted that "objcopy -L" can localize a symbol,
so the dynamic linker wouldn't do the lookup this way. I tried,
but for some reason that didn't seem to work.

Doing the same thing in the linker script instead does seem to
work, though I cannot entirely explain - it *also* works if I
just add "VERSION { { global: *; }; }" instead, indicating that
something else is happening that I don't really understand. It
may be that explicitly doing that marks them with some kind of
empty version, and that's different from the default.

Explicitly marking them with a version breaks kallsyms, so that
doesn't seem to be possible.

Marking all the symbols as local seems correct, and does seem
to address the issue, so do that. Also do it for static link,
nsswitch libraries could still be loaded there.

[1] https://bugs.debian.org/983379

Reported-by: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
Acked-By: Anton Ivanov <[email protected]>
Tested-By: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
sysopenci pushed a commit that referenced this pull request Nov 8, 2023
…_net()

syzbot reported a warning like below [1]:

WARNING: CPU: 3 PID: 9 at net/netfilter/nf_tables_api.c:10096 nf_tables_exit_net+0x71c/0x840
Modules linked in:
CPU: 2 PID: 9 Comm: kworker/u8:0 Tainted: G        W          6.1.0-rc3-00072-g8e5423e991e8 #47
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:nf_tables_exit_net+0x71c/0x840
...
Call Trace:
 <TASK>
 ? __nft_release_table+0xfc0/0xfc0
 ops_exit_list+0xb5/0x180
 cleanup_net+0x506/0xb10
 ? unregister_pernet_device+0x80/0x80
 process_one_work+0xa38/0x1730
 ? pwq_dec_nr_in_flight+0x2b0/0x2b0
 ? rwlock_bug.part.0+0x90/0x90
 ? _raw_spin_lock_irq+0x46/0x50
 worker_thread+0x67e/0x10e0
 ? process_one_work+0x1730/0x1730
 kthread+0x2e5/0x3a0
 ? kthread_complete_and_exit+0x40/0x40
 ret_from_fork+0x1f/0x30
 </TASK>

In nf_tables_exit_net(), there is a case where nft_net->commit_list is
empty but nft_net->module_list is not empty.  Such a case occurs with
the following scenario:

1. nfnetlink_rcv_batch() is called
2. nf_tables_newset() returns -EAGAIN and NFNL_BATCH_FAILURE bit is
   set to status
3. nf_tables_abort() is called with NFNL_ABORT_AUTOLOAD
   (nft_net->commit_list is released, but nft_net->module_list is not
   because of NFNL_ABORT_AUTOLOAD flag)
4. Jump to replay label
5. netlink_skb_clone() fails and returns from the function (this is
   caused by fault injection in the reproducer of syzbot)

This patch fixes this issue by calling __nf_tables_abort() when
nft_net->module_list is not empty in nf_tables_exit_net().

Fixes: eb014de4fd41 ("netfilter: nf_tables: autoload modules from the abort path")
Link: https://syzkaller.appspot.com/bug?id=802aba2422de4218ad0c01b46c9525cc9d4e4aa3 [1]
Reported-by: [email protected]
Signed-off-by: Shigeru Yoshida <[email protected]>
Signed-off-by: Florian Westphal <[email protected]>
(cherry picked from commit 03c1f1ef1584c981935fab2fa0c45d3e43e2c235)

BUG=None
TEST=None

Signed-off-by: Linux Patches Robot <linux-patches-robot@chromeos-missing-patches.google.com.iam.gserviceaccount.com>
Change-Id: I73ae0fd0869365486129f7525555f24de513b76d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/4730729
Reviewed-by: Tzung-Bi Shih <[email protected]>
Reviewed-by: Sean Paul <[email protected]>
Commit-Queue: Tzung-Bi Shih <[email protected]>
@sysopenci sysopenci added the Stale Stale label for inactive open prs label Sep 5, 2024
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