BACKPORT: net/sched: cls_u32: fix netns refcount changes in u32_change()
commit 3db09e762dc79584a69c10d74a6b98f89a9979f8 upstream.
We are now able to detect extra put_net() at the moment
they happen, instead of much later in correct code paths.
u32_init_knode() / tcf_exts_init() populates the ->exts.net
pointer, but as mentioned in tcf_exts_init(),
the refcount on netns has not been elevated yet.
The refcount is taken only once tcf_exts_get_net()
is called.
So the two u32_destroy_key() calls from u32_change()
are attempting to release an invalid reference on the netns.
syzbot report:
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 0 PID: 21708 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Modules linked in:
CPU: 0 PID: 21708 Comm: syz-executor.5 Not tainted 5.18.0-rc2-next-20220412-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Code: 1d 14 b6 b2 09 31 ff 89 de e8 6d e9 89 fd 84 db 75 e0 e8 84 e5 89 fd 48 c7 c7 40 aa 26 8a c6 05 f4 b5 b2 09 01 e8 e5 81 2e 05 <0f> 0b eb c4 e8 68 e5 89 fd 0f b6 1d e3 b5 b2 09 31 ff 89 de e8 38
RSP: 0018:ffffc900051af1b0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff8160a0c8 RDI: fffff52000a35e28
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff81604a9e R11: 0000000000000000 R12: 1ffff92000a35e3b
R13: 00000000ffffffef R14: ffff8880211a0194 R15: ffff8880577d0a00
FS: 00007f25d183e700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f19c859c028 CR3: 0000000051009000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__refcount_dec include/linux/refcount.h:344 [inline]
refcount_dec include/linux/refcount.h:359 [inline]
ref_tracker_free+0x535/0x6b0 lib/ref_tracker.c:118
netns_tracker_free include/net/net_namespace.h:327 [inline]
put_net_track include/net/net_namespace.h:341 [inline]
tcf_exts_put_net include/net/pkt_cls.h:255 [inline]
u32_destroy_key.isra.0+0xa7/0x2b0 net/sched/cls_u32.c:394
u32_change+0xe01/0x3140 net/sched/cls_u32.c:909
tc_new_tfilter+0x98d/0x2200 net/sched/cls_api.c:2148
rtnetlink_rcv_msg+0x80d/0xb80 net/core/rtnetlink.c:6016
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2495
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1921
sock_sendmsg_nosec net/socket.c:705 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:725
____sys_sendmsg+0x6e2/0x800 net/socket.c:2413
___sys_sendmsg+0xf3/0x170 net/socket.c:2467
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f25d0689049
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f25d183e168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f25d079c030 RCX: 00007f25d0689049
RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000005
RBP: 00007f25d06e308d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd0b752e3f R14: 00007f25d183e300 R15: 0000000000022000
</TASK>
Bug: 233075473
Fixes: 35c55fc156d8 ("cls_u32: use tcf_exts_get_net() before call_rcu()")
Signed-off-by: Eric Dumazet <[email protected]>
Reported-by: syzbot <[email protected]>
Cc: Cong Wang <[email protected]>
Cc: Jiri Pirko <[email protected]>
Acked-by: Jamal Hadi Salim <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
Change-Id: I7b19da654a2615bf602d692fe0f5f91e3d33c371
(cherry picked from commit b5a54d8de219f9affbd98e94ccdbaa7781e7a555)
BEST: Make all of your changes to upstream Linux. If appropriate, backport to the stable releases. These patches will be merged automatically in the corresponding common kernels. If the patch is already in upstream Linux, post a backport of the patch that conforms to the patch requirements below.
EXPORT_SYMBOL_GPL() require an in-tree modular driver that uses the symbol -- so include the new driver or changes to an existing driver in the same patchset as the export.LESS GOOD: Develop your patches out-of-tree (from an upstream Linux point-of-view). Unless these are fixing an Android-specific bug, these are very unlikely to be accepted unless they have been coordinated with [email protected]. If you want to proceed, post a patch that conforms to the patch requirements below.
script/checkpatch.plUPSTREAM:, BACKPORT:, FROMGIT:, FROMLIST:, or ANDROID:.Change-Id: tag (see https://gerrit-review.googlesource.com/Documentation/user-changeid.html)Bug: tag.Signed-off-by: tag by the author and the submitterAdditional requirements are listed below based on patch type
UPSTREAM:, BACKPORT:UPSTREAM:.(cherry picked from commit ...) line important patch from upstream
This is the detailed description of the important patch
Signed-off-by: Fred Jones <[email protected]>
- then Joe Smith would upload the patch for the common kernel as
UPSTREAM: important patch from upstream
This is the detailed description of the important patch
Signed-off-by: Fred Jones <[email protected]>
Bug: 135791357
Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
(cherry picked from commit c31e73121f4c1ec41143423ac6ce3ce6dafdcec1)
Signed-off-by: Joe Smith <[email protected]>
BACKPORT: instead of UPSTREAM:.UPSTREAM:(cherry picked from commit ...) line BACKPORT: important patch from upstream
This is the detailed description of the important patch
Signed-off-by: Fred Jones <[email protected]>
Bug: 135791357
Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
(cherry picked from commit c31e73121f4c1ec41143423ac6ce3ce6dafdcec1)
[joe: Resolved minor conflict in drivers/foo/bar.c ]
Signed-off-by: Joe Smith <[email protected]>
FROMGIT:, FROMLIST:,FROMGIT:(cherry picked from commit <sha1> <repo> <branch>). This must be a stable maintainer branch (not rebased, so don't use linux-next for example).BACKPORT: FROMGIT: important patch from upstream
This is the detailed description of the important patch
Signed-off-by: Fred Jones <[email protected]>
- then Joe Smith would upload the patch for the common kernel as
FROMGIT: important patch from upstream
This is the detailed description of the important patch
Signed-off-by: Fred Jones <[email protected]>
Bug: 135791357
(cherry picked from commit 878a2fd9de10b03d11d2f622250285c7e63deace
https://git.kernel.org/pub/scm/linux/kernel/git/foo/bar.git test-branch)
Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
Signed-off-by: Joe Smith <[email protected]>
FROMLIST:Link: tag with a link to the submittal on lore.kernel.orgBug: tag with the Android bug (required for patches not accepted into a maintainer tree)BACKPORT: FROMLIST: FROMLIST: important patch from upstream
This is the detailed description of the important patch
Signed-off-by: Fred Jones <[email protected]>
Bug: 135791357
Link: https://lore.kernel.org/lkml/[email protected]/
Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
Signed-off-by: Joe Smith <[email protected]>
ANDROID:ANDROID:Fixes: tag that cites the patch with the bug ANDROID: fix android-specific bug in foobar.c
This is the detailed description of the important fix
Fixes: 1234abcd2468 ("foobar: add cool feature")
Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
Signed-off-by: Joe Smith <[email protected]>
ANDROID:Bug: tag with the Android bug (required for android-specific features)