Commit Graph

5 Commits

Author SHA1 Message Date
Dan Carpenter e36958eb15 AX.25: Prevent integer overflows in connect and sendmsg
[ Upstream commit 17ad73e941b71f3bec7523ea4e9cbc3752461c2d ]

We recently added some bounds checking in ax25_connect() and
ax25_sendmsg() and we so we removed the AX25_MAX_DIGIS checks because
they were no longer required.

Unfortunately, I believe they are required to prevent integer overflows
so I have added them back.

Fixes: 8885bb0621f0 ("AX.25: Prevent out-of-bounds read in ax25_sendmsg()")
Fixes: 2f2a7ffad5c6 ("AX.25: Fix out-of-bounds read in ax25_connect()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:32:42 +08:00
Peilin Ye 1c8172f655 AX.25: Prevent out-of-bounds read in ax25_sendmsg()
[ Upstream commit 8885bb0621f01a6c82be60a91e5fc0f6e2f71186 ]

Checks on `addr_len` and `usax->sax25_ndigis` are insufficient.
ax25_sendmsg() can go out of bounds when `usax->sax25_ndigis` equals to 7
or 8. Fix it.

It is safe to remove `usax->sax25_ndigis > AX25_MAX_DIGIS`, since
`addr_len` is guaranteed to be less than or equal to
`sizeof(struct full_sockaddr_ax25)`

Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:32:40 +08:00
Peilin Ye ff3c8cb47a AX.25: Fix out-of-bounds read in ax25_connect()
[ Upstream commit 2f2a7ffad5c6cbf3d438e813cfdc88230e185ba6 ]

Checks on `addr_len` and `fsa->fsa_ax25.sax25_ndigis` are insufficient.
ax25_connect() can go out of bounds when `fsa->fsa_ax25.sax25_ndigis`
equals to 7 or 8. Fix it.

This issue has been reported as a KMSAN uninit-value bug, because in such
a case, ax25_connect() reaches into the uninitialized portion of the
`struct sockaddr_storage` statically allocated in __sys_connect().

It is safe to remove `fsa->fsa_ax25.sax25_ndigis > AX25_MAX_DIGIS` because
`addr_len` is guaranteed to be less than or equal to
`sizeof(struct full_sockaddr_ax25)`.

Reported-by: syzbot+c82752228ed975b0a623@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=55ef9d629f3b3d7d70b69558015b63b48d01af66
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:32:40 +08:00
Eric Dumazet 6091bb5404 ax25: fix setsockopt(SO_BINDTODEVICE)
[ Upstream commit 687775cec056b38a4c8f3291e0dd7a9145f7b667 ]

syzbot was able to trigger this trace [1], probably by using
a zero optlen.

While we are at it, cap optlen to IFNAMSIZ - 1 instead of IFNAMSIZ.

[1]
BUG: KMSAN: uninit-value in strnlen+0xf9/0x170 lib/string.c:569
CPU: 0 PID: 8807 Comm: syz-executor483 Not tainted 5.7.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 strnlen+0xf9/0x170 lib/string.c:569
 dev_name_hash net/core/dev.c:207 [inline]
 netdev_name_node_lookup net/core/dev.c:277 [inline]
 __dev_get_by_name+0x75/0x2b0 net/core/dev.c:778
 ax25_setsockopt+0xfa3/0x1170 net/ax25/af_ax25.c:654
 __compat_sys_setsockopt+0x4ed/0x910 net/compat.c:403
 __do_compat_sys_setsockopt net/compat.c:413 [inline]
 __se_compat_sys_setsockopt+0xdd/0x100 net/compat.c:410
 __ia32_compat_sys_setsockopt+0x62/0x80 net/compat.c:410
 do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline]
 do_fast_syscall_32+0x3bf/0x6d0 arch/x86/entry/common.c:398
 entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f57dd9
Code: 90 e8 0b 00 00 00 f3 90 0f ae e8 eb f9 8d 74 26 00 89 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000ffae8c1c EFLAGS: 00000217 ORIG_RAX: 000000000000016e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000101
RDX: 0000000000000019 RSI: 0000000020000000 RDI: 0000000000000004
RBP: 0000000000000012 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Local variable ----devname@ax25_setsockopt created at:
 ax25_setsockopt+0xe6/0x1170 net/ax25/af_ax25.c:536
 ax25_setsockopt+0xe6/0x1170 net/ax25/af_ax25.c:536

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:28:22 +08:00
Kaixu Xia 590eaf1fec Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
2021-03-16 11:01:34 +08:00