linux.git/net/smc, branch v6.16

smc: Fix various oops due to inet_sock type confusion.

2025-07-15T00:12:42+00:00

syzbot reported weird splats [0][1] in cipso_v4_sock_setattr() while
freeing inet_sk(sk)->inet_opt.

The address was freed multiple times even though it was read-only memory.

cipso_v4_sock_setattr() did nothing wrong, and the root cause was type
confusion.

The cited commit made it possible to create smc_sock as an INET socket.

The issue is that struct smc_sock does not have struct inet_sock as the
first member but hijacks AF_INET and AF_INET6 sk_family, which confuses
various places.

In this case, inet_sock.inet_opt was actually smc_sock.clcsk_data_ready(),
which is an address of a function in the text segment.

  $ pahole -C inet_sock vmlinux
  struct inet_sock {
  ...
          struct ip_options_rcu *    inet_opt;             /*   784     8 */

  $ pahole -C smc_sock vmlinux
  struct smc_sock {
  ...
          void                       (*clcsk_data_ready)(struct sock *); /*   784     8 */

The same issue for another field was reported before. [2][3]

At that time, an ugly hack was suggested [4], but it makes both INET
and SMC code error-prone and hard to change.

Also, yet another variant was fixed by a hacky commit 98d4435efcbf3
("net/smc: prevent NULL pointer dereference in txopt_get").

Instead of papering over the root cause by such hacks, we should not
allow non-INET socket to reuse the INET infra.

Let's add inet_sock as the first member of smc_sock.

[0]:
kvfree_call_rcu(): Double-freed call. rcu_head 000000006921da73
WARNING: CPU: 0 PID: 6718 at mm/slab_common.c:1956 kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955
Modules linked in:
CPU: 0 UID: 0 PID: 6718 Comm: syz.0.17 Tainted: G        W           6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955
lr : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955
sp : ffff8000a03a7730
x29: ffff8000a03a7730 x28: 00000000fffffff5 x27: 1fffe000184823d3
x26: dfff800000000000 x25: ffff0000c2411e9e x24: ffff0000dd88da00
x23: ffff8000891ac9a0 x22: 00000000ffffffea x21: ffff8000891ac9a0
x20: ffff8000891ac9a0 x19: ffff80008afc2480 x18: 00000000ffffffff
x17: 0000000000000000 x16: ffff80008ae642c8 x15: ffff700011ede14c
x14: 1ffff00011ede14c x13: 0000000000000004 x12: ffffffffffffffff
x11: ffff700011ede14c x10: 0000000000ff0100 x9 : 5fa3c1ffaf0ff000
x8 : 5fa3c1ffaf0ff000 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000a03a7078 x4 : ffff80008f766c20 x3 : ffff80008054d360
x2 : 0000000000000000 x1 : 0000000000000201 x0 : 0000000000000000
Call trace:
 kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955 (P)
 cipso_v4_sock_setattr+0x2f0/0x3f4 net/ipv4/cipso_ipv4.c:1914
 netlbl_sock_setattr+0x240/0x334 net/netlabel/netlabel_kapi.c:1000
 smack_netlbl_add+0xa8/0x158 security/smack/smack_lsm.c:2581
 smack_inode_setsecurity+0x378/0x430 security/smack/smack_lsm.c:2912
 security_inode_setsecurity+0x118/0x3c0 security/security.c:2706
 __vfs_setxattr_noperm+0x174/0x5c4 fs/xattr.c:251
 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:295
 vfs_setxattr+0x158/0x2ac fs/xattr.c:321
 do_setxattr fs/xattr.c:636 [inline]
 file_setxattr+0x1b8/0x294 fs/xattr.c:646
 path_setxattrat+0x2ac/0x320 fs/xattr.c:711
 __do_sys_fsetxattr fs/xattr.c:761 [inline]
 __se_sys_fsetxattr fs/xattr.c:758 [inline]
 __arm64_sys_fsetxattr+0xc0/0xdc fs/xattr.c:758
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

[1]:
Unable to handle kernel write to read-only memory at virtual address ffff8000891ac9a8
KASAN: probably user-memory-access in range [0x0000000448d64d40-0x0000000448d64d47]
Mem abort info:
  ESR = 0x000000009600004e
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x0e: level 2 permission fault
Data abort info:
  ISV = 0, ISS = 0x0000004e, ISS2 = 0x00000000
  CM = 0, WnR = 1, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000207144000
[ffff8000891ac9a8] pgd=0000000000000000, p4d=100000020f950003, pud=100000020f951003, pmd=0040000201000781
Internal error: Oops: 000000009600004e [#1]  SMP
Modules linked in:
CPU: 0 UID: 0 PID: 6946 Comm: syz.0.69 Not tainted 6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : kvfree_call_rcu+0x31c/0x3f0 mm/slab_common.c:1971
lr : add_ptr_to_bulk_krc_lock mm/slab_common.c:1838 [inline]
lr : kvfree_call_rcu+0xfc/0x3f0 mm/slab_common.c:1963
sp : ffff8000a28a7730
x29: ffff8000a28a7730 x28: 00000000fffffff5 x27: 1fffe00018b09bb3
x26: 0000000000000001 x25: ffff80008f66e000 x24: ffff00019beaf498
x23: ffff00019beaf4c0 x22: 0000000000000000 x21: ffff8000891ac9a0
x20: ffff8000891ac9a0 x19: 0000000000000000 x18: 00000000ffffffff
x17: ffff800093363000 x16: ffff80008052c6e4 x15: ffff700014514ecc
x14: 1ffff00014514ecc x13: 0000000000000004 x12: ffffffffffffffff
x11: ffff700014514ecc x10: 0000000000000001 x9 : 0000000000000001
x8 : ffff00019beaf7b4 x7 : ffff800080a94154 x6 : 0000000000000000
x5 : ffff8000935efa60 x4 : 0000000000000008 x3 : ffff80008052c7fc
x2 : 0000000000000001 x1 : ffff8000891ac9a0 x0 : 0000000000000001
Call trace:
 kvfree_call_rcu+0x31c/0x3f0 mm/slab_common.c:1967 (P)
 cipso_v4_sock_setattr+0x2f0/0x3f4 net/ipv4/cipso_ipv4.c:1914
 netlbl_sock_setattr+0x240/0x334 net/netlabel/netlabel_kapi.c:1000
 smack_netlbl_add+0xa8/0x158 security/smack/smack_lsm.c:2581
 smack_inode_setsecurity+0x378/0x430 security/smack/smack_lsm.c:2912
 security_inode_setsecurity+0x118/0x3c0 security/security.c:2706
 __vfs_setxattr_noperm+0x174/0x5c4 fs/xattr.c:251
 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:295
 vfs_setxattr+0x158/0x2ac fs/xattr.c:321
 do_setxattr fs/xattr.c:636 [inline]
 file_setxattr+0x1b8/0x294 fs/xattr.c:646
 path_setxattrat+0x2ac/0x320 fs/xattr.c:711
 __do_sys_fsetxattr fs/xattr.c:761 [inline]
 __se_sys_fsetxattr fs/xattr.c:758 [inline]
 __arm64_sys_fsetxattr+0xc0/0xdc fs/xattr.c:758
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Code: aa1f03e2 52800023 97ee1e8d b4000195 (f90006b4)

Fixes: d25a92ccae6b ("net/smc: Introduce IPPROTO_SMC")
Reported-by: syzbot+40bf00346c3fe40f90f2@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/686d9b50.050a0220.1ffab7.0020.GAE@google.com/
Tested-by: syzbot+40bf00346c3fe40f90f2@syzkaller.appspotmail.com
Reported-by: syzbot+f22031fad6cbe52c70e7@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/686da0f3.050a0220.1ffab7.0022.GAE@google.com/
Reported-by: syzbot+271fed3ed6f24600c364@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=271fed3ed6f24600c364 # [2]
Link: https://lore.kernel.org/netdev/99f284be-bf1d-4bc4-a629-77b268522fff@huawei.com/ # [3]
Link: https://lore.kernel.org/netdev/20250331081003.1503211-1-wangliang74@huawei.com/ # [4]
Signed-off-by: Kuniyuki Iwashima 
Reviewed-by: D. Wythe 
Reviewed-by: Wang Liang 
Link: https://patch.msgid.link/20250711060808.2977529-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski

smc: Fix lockdep false-positive for IPPROTO_SMC.

2025-04-11T21:14:26+00:00

SMC consists of two sockets: smc_sock and kernel TCP socket.

Currently, there are two ways of creating the sockets, and syzbot reported
a lockdep splat [0] for the newer way introduced by commit d25a92ccae6b
("net/smc: Introduce IPPROTO_SMC").

  socket(AF_SMC             , SOCK_STREAM, SMCPROTO_SMC or SMCPROTO_SMC6)
  socket(AF_INET or AF_INET6, SOCK_STREAM, IPPROTO_SMC)

When a socket is allocated, sock_lock_init() sets a lockdep lock class to
sk->sk_lock.slock based on its protocol family.  In the IPPROTO_SMC case,
AF_INET or AF_INET6 lock class is assigned to smc_sock.

The repro sets IPV6_JOIN_ANYCAST for IPv6 UDP and SMC socket and exercises
smc_switch_to_fallback() for IPPROTO_SMC.

  1. smc_switch_to_fallback() is called under lock_sock() and holds
     smc->clcsock_release_lock.

      sk_lock-AF_INET6 -> &smc->clcsock_release_lock
      (sk_lock-AF_SMC)

  2. Setting IPV6_JOIN_ANYCAST to SMC holds smc->clcsock_release_lock
     and calls setsockopt() for the kernel TCP socket, which holds RTNL
     and the kernel socket's lock_sock().

      &smc->clcsock_release_lock -> rtnl_mutex (-> k-sk_lock-AF_INET6)

  3. Setting IPV6_JOIN_ANYCAST to UDP holds RTNL and lock_sock().

      rtnl_mutex -> sk_lock-AF_INET6

Then, lockdep detects a false-positive circular locking,

  .-> sk_lock-AF_INET6 -> &smc->clcsock_release_lock -> rtnl_mutex -.
  `-----------------------------------------------------------------'

but IPPROTO_SMC should have the same locking rule as AF_SMC.

      sk_lock-AF_SMC   -> &smc->clcsock_release_lock -> rtnl_mutex -> k-sk_lock-AF_INET6

Let's set the same lock class for smc_sock.

Given AF_SMC uses the same lock class for SMCPROTO_SMC and SMCPROTO_SMC6,
we do not need to separate the class for AF_INET and AF_INET6.

[0]:
WARNING: possible circular locking dependency detected
6.14.0-rc3-syzkaller-00267-gff202c5028a1 #0 Not tainted

syz.4.1528/11571 is trying to acquire lock:
ffffffff8fef8de8 (rtnl_mutex){+.+.}-{4:4}, at: ipv6_sock_ac_close+0xd9/0x110 net/ipv6/anycast.c:220

but task is already holding lock:
ffff888027f596a8 (&smc->clcsock_release_lock){+.+.}-{4:4}, at: smc_clcsock_release+0x75/0xe0 net/smc/smc_close.c:30

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

 -> #2 (&smc->clcsock_release_lock){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
       smc_switch_to_fallback+0x2d/0xa00 net/smc/af_smc.c:903
       smc_sendmsg+0x13d/0x520 net/smc/af_smc.c:2781
       sock_sendmsg_nosec net/socket.c:718 [inline]
       __sock_sendmsg net/socket.c:733 [inline]
       ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2573
       ___sys_sendmsg+0x135/0x1e0 net/socket.c:2627
       __sys_sendmsg+0x16e/0x220 net/socket.c:2659
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

 -> #1 (sk_lock-AF_INET6){+.+.}-{0:0}:
       lock_sock_nested+0x3a/0xf0 net/core/sock.c:3645
       lock_sock include/net/sock.h:1624 [inline]
       sockopt_lock_sock net/core/sock.c:1133 [inline]
       sockopt_lock_sock+0x54/0x70 net/core/sock.c:1124
       do_ipv6_setsockopt+0x2160/0x4520 net/ipv6/ipv6_sockglue.c:567
       ipv6_setsockopt+0xcb/0x170 net/ipv6/ipv6_sockglue.c:993
       udpv6_setsockopt+0x7d/0xd0 net/ipv6/udp.c:1850
       do_sock_setsockopt+0x222/0x480 net/socket.c:2303
       __sys_setsockopt+0x1a0/0x230 net/socket.c:2328
       __do_sys_setsockopt net/socket.c:2334 [inline]
       __se_sys_setsockopt net/socket.c:2331 [inline]
       __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2331
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

 -> #0 (rtnl_mutex){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3163 [inline]
       check_prevs_add kernel/locking/lockdep.c:3282 [inline]
       validate_chain kernel/locking/lockdep.c:3906 [inline]
       __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228
       lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
       ipv6_sock_ac_close+0xd9/0x110 net/ipv6/anycast.c:220
       inet6_release+0x47/0x70 net/ipv6/af_inet6.c:485
       __sock_release net/socket.c:647 [inline]
       sock_release+0x8e/0x1d0 net/socket.c:675
       smc_clcsock_release+0xb7/0xe0 net/smc/smc_close.c:34
       __smc_release+0x5c2/0x880 net/smc/af_smc.c:301
       smc_release+0x1fc/0x5f0 net/smc/af_smc.c:344
       __sock_release+0xb0/0x270 net/socket.c:647
       sock_close+0x1c/0x30 net/socket.c:1398
       __fput+0x3ff/0xb70 fs/file_table.c:464
       task_work_run+0x14e/0x250 kernel/task_work.c:227
       resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
       exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
       __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
       syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
       do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  rtnl_mutex --> sk_lock-AF_INET6 --> &smc->clcsock_release_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&smc->clcsock_release_lock);
                               lock(sk_lock-AF_INET6);
                               lock(&smc->clcsock_release_lock);
  lock(rtnl_mutex);

 *** DEADLOCK ***

2 locks held by syz.4.1528/11571:
 #0: ffff888077e88208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
 #0: ffff888077e88208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:646
 #1: ffff888027f596a8 (&smc->clcsock_release_lock){+.+.}-{4:4}, at: smc_clcsock_release+0x75/0xe0 net/smc/smc_close.c:30

stack backtrace:
CPU: 0 UID: 0 PID: 11571 Comm: syz.4.1528 Not tainted 6.14.0-rc3-syzkaller-00267-gff202c5028a1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_circular_bug+0x490/0x760 kernel/locking/lockdep.c:2076
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2208
 check_prev_add kernel/locking/lockdep.c:3163 [inline]
 check_prevs_add kernel/locking/lockdep.c:3282 [inline]
 validate_chain kernel/locking/lockdep.c:3906 [inline]
 __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851
 __mutex_lock_common kernel/locking/mutex.c:585 [inline]
 __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
 ipv6_sock_ac_close+0xd9/0x110 net/ipv6/anycast.c:220
 inet6_release+0x47/0x70 net/ipv6/af_inet6.c:485
 __sock_release net/socket.c:647 [inline]
 sock_release+0x8e/0x1d0 net/socket.c:675
 smc_clcsock_release+0xb7/0xe0 net/smc/smc_close.c:34
 __smc_release+0x5c2/0x880 net/smc/af_smc.c:301
 smc_release+0x1fc/0x5f0 net/smc/af_smc.c:344
 __sock_release+0xb0/0x270 net/socket.c:647
 sock_close+0x1c/0x30 net/socket.c:1398
 __fput+0x3ff/0xb70 fs/file_table.c:464
 task_work_run+0x14e/0x250 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8b4b38d169
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe4efd22d8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00000000000b14a3 RCX: 00007f8b4b38d169
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f8b4b5a7ba0 R08: 0000000000000001 R09: 000000114efd25cf
R10: 00007f8b4b200000 R11: 0000000000000246 R12: 00007f8b4b5a5fac
R13: 00007f8b4b5a5fa0 R14: ffffffffffffffff R15: 00007ffe4efd23f0
 

Fixes: d25a92ccae6b ("net/smc: Introduce IPPROTO_SMC")
Reported-by: syzbot+be6f4b383534d88989f7@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=be6f4b383534d88989f7
Signed-off-by: Kuniyuki Iwashima 
Reviewed-by: Wenjia Zhang 
Link: https://patch.msgid.link/20250407170332.26959-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski

net/smc: use the correct ndev to find pnetid by pnetid table

2025-03-14T12:54:40+00:00

When using smc_pnet in SMC, it will only search the pnetid in the
base_ndev of the netdev hierarchy(both HW PNETID and User-defined
sw pnetid). This may not work for some scenarios when using SMC in
container on cloud environment.
In container, there have choices of different container network,
such as directly using host network, virtual network IPVLAN, veth,
etc. Different choices of container network have different netdev
hierarchy. Examples of netdev hierarchy show below. (eth0 and eth1
in host below is the netdev directly related to the physical device).
            _______________________________
           |   _________________           |
           |  |POD              |          |
           |  |                 |          |
           |  | eth0_________   |          |
           |  |____|         |__|          |
           |       |         |             |
           |       |         |             |
           |   eth1|base_ndev| eth0_______ |
           |       |         |    | RDMA  ||
           | host  |_________|    |_______||
           ---------------------------------
     netdev hierarchy if directly using host network
           ________________________________
           |   _________________           |
           |  |POD  __________  |          |
           |  |    |upper_ndev| |          |
           |  |eth0|__________| |          |
           |  |_______|_________|          |
           |          |lower netdev        |
           |        __|______              |
           |   eth1|         | eth0_______ |
           |       |base_ndev|    | RDMA  ||
           | host  |_________|    |_______||
           ---------------------------------
            netdev hierarchy if using IPVLAN
            _______________________________
           |   _____________________       |
           |  |POD        _________ |      |
           |  |          |base_ndev||      |
           |  |eth0(veth)|_________||      |
           |  |____________|________|      |
           |               |pairs          |
           |        _______|_              |
           |       |         | eth0_______ |
           |   veth|base_ndev|    | RDMA  ||
           |       |_________|    |_______||
           |        _________              |
           |   eth1|base_ndev|             |
           | host  |_________|             |
           ---------------------------------
             netdev hierarchy if using veth
Due to some reasons, the eth1 in host is not RDMA attached netdevice,
pnetid is needed to map the eth1(in host) with RDMA device so that POD
can do SMC-R. Because the eth1(in host) is managed by CNI plugin(such
as Terway, network management plugin in container environment), and in
cloud environment the eth(in host) can dynamically be inserted by CNI
when POD create and dynamically be removed by CNI when POD destroy and
no POD related to the eth(in host) anymore. It is hard to config the
pnetid to the eth1(in host). But it is easy to config the pnetid to the
netdevice which can be seen in POD. When do SMC-R, both the container
directly using host network and the container using veth network can
successfully match the RDMA device, because the configured pnetid netdev
is a base_ndev. But the container using IPVLAN can not successfully
match the RDMA device and 0x03030000 fallback happens, because the
configured pnetid netdev is not a base_ndev. Additionally, if config
pnetid to the eth1(in host) also can not work for matching RDMA device
when using veth network and doing SMC-R in POD.

To resolve the problems list above, this patch extends to search user
-defined sw pnetid in the clc handshake ndev when no pnetid can be found
in the base_ndev, and the base_ndev take precedence over ndev for backward
compatibility. This patch also can unify the pnetid setup of different
network choices list above in container(Config user-defined sw pnetid in
the netdevice can be seen in POD).

Signed-off-by: Guangguan Wang 
Reviewed-by: Wenjia Zhang 
Reviewed-by: Halil Pasic 
Signed-off-by: David S. Miller

net: better track kernel sockets lifetime

2025-02-22T00:00:58+00:00

While kernel sockets are dismantled during pernet_operations->exit(),
their freeing can be delayed by any tx packets still held in qdisc
or device queues, due to skb_set_owner_w() prior calls.

This then trigger the following warning from ref_tracker_dir_exit() [1]

To fix this, make sure that kernel sockets own a reference on net->passive.

Add sk_net_refcnt_upgrade() helper, used whenever a kernel socket
is converted to a refcounted one.

[1]

[  136.263918][   T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at
[  136.263918][   T35]      sk_alloc+0x2b3/0x370
[  136.263918][   T35]      inet6_create+0x6ce/0x10f0
[  136.263918][   T35]      __sock_create+0x4c0/0xa30
[  136.263918][   T35]      inet_ctl_sock_create+0xc2/0x250
[  136.263918][   T35]      igmp6_net_init+0x39/0x390
[  136.263918][   T35]      ops_init+0x31e/0x590
[  136.263918][   T35]      setup_net+0x287/0x9e0
[  136.263918][   T35]      copy_net_ns+0x33f/0x570
[  136.263918][   T35]      create_new_namespaces+0x425/0x7b0
[  136.263918][   T35]      unshare_nsproxy_namespaces+0x124/0x180
[  136.263918][   T35]      ksys_unshare+0x57d/0xa70
[  136.263918][   T35]      __x64_sys_unshare+0x38/0x40
[  136.263918][   T35]      do_syscall_64+0xf3/0x230
[  136.263918][   T35]      entry_SYSCALL_64_after_hwframe+0x77/0x7f
[  136.263918][   T35]
[  136.343488][   T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at
[  136.343488][   T35]      sk_alloc+0x2b3/0x370
[  136.343488][   T35]      inet6_create+0x6ce/0x10f0
[  136.343488][   T35]      __sock_create+0x4c0/0xa30
[  136.343488][   T35]      inet_ctl_sock_create+0xc2/0x250
[  136.343488][   T35]      ndisc_net_init+0xa7/0x2b0
[  136.343488][   T35]      ops_init+0x31e/0x590
[  136.343488][   T35]      setup_net+0x287/0x9e0
[  136.343488][   T35]      copy_net_ns+0x33f/0x570
[  136.343488][   T35]      create_new_namespaces+0x425/0x7b0
[  136.343488][   T35]      unshare_nsproxy_namespaces+0x124/0x180
[  136.343488][   T35]      ksys_unshare+0x57d/0xa70
[  136.343488][   T35]      __x64_sys_unshare+0x38/0x40
[  136.343488][   T35]      do_syscall_64+0xf3/0x230
[  136.343488][   T35]      entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: 0cafd77dcd03 ("net: add a refcount tracker for kernel sockets")
Reported-by: syzbot+30a19e01a97420719891@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/67b72aeb.050a0220.14d86d.0283.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet 
Reviewed-by: Kuniyuki Iwashima 
Link: https://patch.msgid.link/20250220131854.4048077-1-edumazet@google.com
Signed-off-by: Jakub Kicinski

net/smc: fix data error when recvmsg with MSG_PEEK flag

2025-01-14T02:59:00+00:00

When recvmsg with MSG_PEEK flag, the data will be copied to
user's buffer without advancing consume cursor and without
reducing the length of rx available data. Once the expected
peek length is larger than the value of bytes_to_rcv, in the
loop of do while in smc_rx_recvmsg, the first loop will copy
bytes_to_rcv bytes of data from the position local_tx_ctrl.cons,
the second loop will copy the min(bytes_to_rcv, read_remaining)
bytes from the position local_tx_ctrl.cons again because of the
lacking of process with advancing consume cursor and reducing
the length of available data. So do the subsequent loops. The
data copied in the second loop and the subsequent loops will
result in data error, as it should not be copied if no more data
arrives and it should be copied from the position advancing
bytes_to_rcv bytes from the local_tx_ctrl.cons if more data arrives.

This issue can be reproduce by the following python script:
server.py:
import socket
import time
server_ip = '0.0.0.0'
server_port = 12346
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.bind((server_ip, server_port))
server_socket.listen(1)
print('Server is running and listening for connections...')
conn, addr = server_socket.accept()
print('Connected by', addr)
while True:
    data = conn.recv(1024)
    if not data:
        break
    print('Received request:', data.decode())
    conn.sendall(b'Hello, client!\n')
    time.sleep(5)
    conn.sendall(b'Hello, again!\n')
conn.close()

client.py:
import socket
server_ip = ''
server_port = 12346
resp=b'Hello, client!\nHello, again!\n'
client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client_socket.connect((server_ip, server_port))
request = 'Hello, server!'
client_socket.sendall(request.encode())
peek_data = client_socket.recv(len(resp),
    socket.MSG_PEEK | socket.MSG_WAITALL)
print('Peeked data:', peek_data.decode())
client_socket.close()

Fixes: 952310ccf2d8 ("smc: receive data from RMBE")
Reported-by: D. Wythe 
Signed-off-by: Guangguan Wang 
Link: https://patch.msgid.link/20250104143201.35529-1-guangguan.wang@linux.alibaba.com
Signed-off-by: Jakub Kicinski

net/smc: delete pointless divide by one

2025-01-11T21:08:54+00:00

Here "buf" is a void pointer so sizeof(*buf) is one.  Doing a divide
by one makes the code less readable.  Delete it.

Signed-off-by: Dan Carpenter 
Reviewed-by: Simon Horman 
Reviewed-by: Kalesh AP 
Link: https://patch.msgid.link/ee1a790b-f874-4512-b3ae-9c45f99dc640@stanley.mountain
Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2024-12-19T19:35:07+00:00

Cross-merge networking fixes after downstream PR (net-6.13-rc4).

No conflicts.

Adjacent changes:

drivers/net/ethernet/renesas/rswitch.h
  32fd46f5b69e ("net: renesas: rswitch: remove speed from gwca structure")
  922b4b955a03 ("net: renesas: rswitch: rework ts tags management")

Signed-off-by: Jakub Kicinski

net/smc: check return value of sock_recvmsg when draining clc data

2024-12-15T12:34:59+00:00

When receiving clc msg, the field length in smc_clc_msg_hdr indicates the
length of msg should be received from network and the value should not be
fully trusted as it is from the network. Once the value of length exceeds
the value of buflen in function smc_clc_wait_msg it may run into deadloop
when trying to drain the remaining data exceeding buflen.

This patch checks the return value of sock_recvmsg when draining data in
case of deadloop in draining.

Fixes: fb4f79264c0f ("net/smc: tolerate future SMCD versions")
Signed-off-by: Guangguan Wang 
Reviewed-by: Wen Gu 
Reviewed-by: D. Wythe 
Signed-off-by: David S. Miller

net/smc: check smcd_v2_ext_offset when receiving proposal msg

2024-12-15T12:34:59+00:00

When receiving proposal msg in server, the field smcd_v2_ext_offset in
proposal msg is from the remote client and can not be fully trusted.
Once the value of smcd_v2_ext_offset exceed the max value, there has
the chance to access wrong address, and crash may happen.

This patch checks the value of smcd_v2_ext_offset before using it.

Fixes: 5c21c4ccafe8 ("net/smc: determine accepted ISM devices")
Signed-off-by: Guangguan Wang 
Reviewed-by: Wen Gu 
Reviewed-by: D. Wythe 
Signed-off-by: David S. Miller

net/smc: check v2_ext_offset/eid_cnt/ism_gid_cnt when receiving proposal msg

2024-12-15T12:34:59+00:00

When receiving proposal msg in server, the fields v2_ext_offset/
eid_cnt/ism_gid_cnt in proposal msg are from the remote client
and can not be fully trusted. Especially the field v2_ext_offset,
once exceed the max value, there has the chance to access wrong
address, and crash may happen.

This patch checks the fields v2_ext_offset/eid_cnt/ism_gid_cnt
before using them.

Fixes: 8c3dca341aea ("net/smc: build and send V2 CLC proposal")
Signed-off-by: Guangguan Wang 
Reviewed-by: Wen Gu 
Reviewed-by: D. Wythe 
Signed-off-by: David S. Miller