Packetdrill: ADD_ADDR are now sent sooner #144

matttbe · 2021-01-23T10:15:18Z

Due to the modifications for #139, ADD_ADDR are now sent sooner but this causes issues in Packetdrill where we still expect ADD_ADDR to come later.

A recent modification of the kernel changes the way ADD_ADDR are sent. See: multipath-tcp/mptcp_net-next#139 In consequences, we have to adapt our tests to have these ADD_ADDR sent earlier, ASAP in fact. We now make sure ADD_ADDR and ADD_ADDR echo are properly sent before injecting MP_JOIN SYN and SYN+ACK or sending data. Closes: multipath-tcp/mptcp_net-next#144 Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>

arm32 uses software to simulate the instruction replaced by kprobe. some instructions may be simulated by constructing assembly functions. therefore, before executing instruction simulation, it is necessary to construct assembly function execution environment in C language through binding registers. after kasan is enabled, the register binding relationship will be destroyed, resulting in instruction simulation errors and causing kernel panic. the kprobe emulate instruction function is distributed in three files: actions-common.c actions-arm.c actions-thumb.c, so disable KASAN when compiling these files. for example, use kprobe insert on cap_capable+20 after kasan enabled, the cap_capable assembly code is as follows: <cap_capable>: e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr} e1a05000 mov r5, r0 e280006c add r0, r0, #108 ; 0x6c e1a04001 mov r4, r1 e1a06002 mov r6, r2 e59fa090 ldr sl, [pc, #144] ; ebfc7bf8 bl c03aa4b4 <__asan_load4> e595706c ldr r7, [r5, #108] ; 0x6c e2859014 add r9, r5, #20 ...... The emulate_ldr assembly code after enabling kasan is as follows: c06f1384 <emulate_ldr>: e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr} e282803c add r8, r2, #60 ; 0x3c e1a05000 mov r5, r0 e7e37855 ubfx r7, r5, #16, #4 e1a00008 mov r0, r8 e1a09001 mov r9, r1 e1a04002 mov r4, r2 ebf35462 bl c03c6530 <__asan_load4> e357000f cmp r7, #15 e7e36655 ubfx r6, r5, #12, #4 e205a00f and sl, r5, #15 0a000001 beq c06f13bc <emulate_ldr+0x38> e0840107 add r0, r4, r7, lsl #2 ebf3545c bl c03c6530 <__asan_load4> e084010a add r0, r4, sl, lsl #2 ebf3545a bl c03c6530 <__asan_load4> e2890010 add r0, r9, #16 ebf35458 bl c03c6530 <__asan_load4> e5990010 ldr r0, [r9, #16] e12fff30 blx r0 e356000f cm r6, #15 1a000014 bne c06f1430 <emulate_ldr+0xac> e1a06000 mov r6, r0 e2840040 add r0, r4, #64 ; 0x40 ...... when running in emulate_ldr to simulate the ldr instruction, panic occurred, and the log is as follows: Unable to handle kernel NULL pointer dereference at virtual address 00000090 pgd = ecb46400 [00000090] *pgd=2e0fa003, *pmd=00000000 Internal error: Oops: 206 [#1] SMP ARM PC is at cap_capable+0x14/0xb0 LR is at emulate_ldr+0x50/0xc0 psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c r10: 00000000 r9 : c30897f4 r8 : ecd63cd4 r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98 r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user Control: 32c5387d Table: 2d546400 DAC: 55555555 Process bash (pid: 1643, stack limit = 0xecd60190) (cap_capable) from (kprobe_handler+0x218/0x340) (kprobe_handler) from (kprobe_trap_handler+0x24/0x48) (kprobe_trap_handler) from (do_undefinstr+0x13c/0x364) (do_undefinstr) from (__und_svc_finish+0x0/0x30) (__und_svc_finish) from (cap_capable+0x18/0xb0) (cap_capable) from (cap_vm_enough_memory+0x38/0x48) (cap_vm_enough_memory) from (security_vm_enough_memory_mm+0x48/0x6c) (security_vm_enough_memory_mm) from (copy_process.constprop.5+0x16b4/0x25c8) (copy_process.constprop.5) from (_do_fork+0xe8/0x55c) (_do_fork) from (SyS_clone+0x1c/0x24) (SyS_clone) from (__sys_trace_return+0x0/0x10) Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7) Fixes: 35aa1df ("ARM kprobes: instruction single-stepping support") Fixes: 4210157 ("ARM: 9017/2: Enable KASan for ARM") Signed-off-by: huangshaobo <huangshaobo6@huawei.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

…ower_limit() There is a global-out-of-bounds reported by KASAN: BUG: KASAN: global-out-of-bounds in _rtl8812ae_eq_n_byte.part.0+0x3d/0x84 [rtl8821ae] Read of size 1 at addr ffffffffa0773c43 by task NetworkManager/411 CPU: 6 PID: 411 Comm: NetworkManager Tainted: G D 6.1.0-rc8+ #144 e15588508517267d37 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), Call Trace: <TASK> ... kasan_report+0xbb/0x1c0 _rtl8812ae_eq_n_byte.part.0+0x3d/0x84 [rtl8821ae] rtl8821ae_phy_bb_config.cold+0x346/0x641 [rtl8821ae] rtl8821ae_hw_init+0x1f5e/0x79b0 [rtl8821ae] ... </TASK> The root cause of the problem is that the comparison order of "prate_section" in _rtl8812ae_phy_set_txpower_limit() is wrong. The _rtl8812ae_eq_n_byte() is used to compare the first n bytes of the two strings from tail to head, which causes the problem. In the _rtl8812ae_phy_set_txpower_limit(), it was originally intended to meet this requirement by carefully designing the comparison order. For example, "pregulation" and "pbandwidth" are compared in order of length from small to large, first is 3 and last is 4. However, the comparison order of "prate_section" dose not obey such order requirement, therefore when "prate_section" is "HT", when comparing from tail to head, it will lead to access out of bounds in _rtl8812ae_eq_n_byte(). As mentioned above, the _rtl8812ae_eq_n_byte() has the same function as strcmp(), so just strcmp() is enough. Fix it by removing _rtl8812ae_eq_n_byte() and use strcmp() barely. Although it can be fixed by adjusting the comparison order of "prate_section", this may cause the value of "rate_section" to not be from 0 to 5. In addition, commit "21e4b0726dc6" not only moved driver from staging to regular tree, but also added setting txpower limit function during the driver config phase, so the problem was introduced by this commit. Fixes: 21e4b07 ("rtlwifi: rtl8821ae: Move driver from staging to regular tree") Signed-off-by: Li Zetao <lizetao1@huawei.com> Acked-by: Ping-Ke Shih <pkshih@realtek.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20221212025812.1541311-1-lizetao1@huawei.com

Older platforms and Virtual platforms which doesn't have support for bluetooth device in ACPI firmware will not have valid ACPI handle. Check for validity of handle before accessing. dmesg log from simics environment (virtual platform): BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: acpi_ns_walk_namespace+0x5c/0x278 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI Modules linked in: bnep intel_powerclamp coretemp kvm_intel kvm irqbypass intel_cstate input_leds joydev serio_raw mac_hid btusb(OE) btintel(OE) bluetooth(OE) lpc_ich compat(OE) ecdh_generic i7core_edac i5500_temp shpchp binfmt_misc sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 hid_generic usbhid hid e1000e psmouse ahci pata_acpi libahci ptp pps_core floppy CPU: 0 PID: 35 Comm: kworker/u3:0 Tainted: G OE 4.15.0-140-generic #144-Ubuntu Hardware name: Simics Simics, BIOS Simics 01/01/2011 Workqueue: hci0 hci_power_on [bluetooth] RIP: 0010:acpi_ns_walk_namespace+0x5c/0x278 RSP: 0000:ffffaa9c0049bba8 EFLAGS: 00010246 RAX: 0000000000000001 RBX: 0000000000001001 RCX: 0000000000000010 RDX: ffffffff92ea7e27 RSI: ffffffff92ea7e10 RDI: 00000000000000c8 RBP: ffffaa9c0049bbf8 R08: 0000000000000000 R09: ffffffffc05b39d0 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000000 R14: ffffffffc05b39d0 R15: ffffaa9c0049bc70 FS: 0000000000000000(0000) GS:ffff8be73fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 0000000075f0e000 CR4: 00000000000006f0 Fixes: 294d749 ("Bluetooth: btintel: Iterate only bluetooth device ACPI entries") Signed-off-by: Kiran K <kiran.k@intel.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc2-ktest-00018-gebd1d148b278 #144 Not tainted ------------------------------------------------------ fio/1345 is trying to acquire lock: ffff88813e200ab8 (&c->snapshot_create_lock){++++}-{3:3}, at: bch2_truncate+0x76/0xf0 but task is already holding lock: ffff888105a1fa38 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: do_truncate+0x7b/0xc0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}: down_write+0x3d/0xd0 bch2_write_iter+0x1c0/0x10f0 vfs_write+0x24a/0x560 __x64_sys_pwrite64+0x77/0xb0 x64_sys_call+0x17e5/0x1ab0 do_syscall_64+0x68/0x130 entry_SYSCALL_64_after_hwframe+0x4b/0x53 -> #1 (sb_writers#10){.+.+}-{0:0}: mnt_want_write+0x4a/0x1d0 filename_create+0x69/0x1a0 user_path_create+0x38/0x50 bch2_fs_file_ioctl+0x315/0xbf0 __x64_sys_ioctl+0x297/0xaf0 x64_sys_call+0x10cb/0x1ab0 do_syscall_64+0x68/0x130 entry_SYSCALL_64_after_hwframe+0x4b/0x53 -> #0 (&c->snapshot_create_lock){++++}-{3:3}: __lock_acquire+0x1445/0x25b0 lock_acquire+0xbd/0x2b0 down_read+0x40/0x180 bch2_truncate+0x76/0xf0 bchfs_truncate+0x240/0x3f0 bch2_setattr+0x7b/0xb0 notify_change+0x322/0x4b0 do_truncate+0x8b/0xc0 do_ftruncate+0x110/0x270 __x64_sys_ftruncate+0x43/0x80 x64_sys_call+0x1373/0x1ab0 do_syscall_64+0x68/0x130 entry_SYSCALL_64_after_hwframe+0x4b/0x53 other info that might help us debug this: Chain exists of: &c->snapshot_create_lock --> sb_writers#10 --> &sb->s_type->i_mutex_key#13 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#13); lock(sb_writers#10); lock(&sb->s_type->i_mutex_key#13); rlock(&c->snapshot_create_lock); *** DEADLOCK *** Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

matttbe added bug packetdrill labels Jan 23, 2021

matttbe self-assigned this Jan 23, 2021

matttbe mentioned this issue Jan 23, 2021

mptcp: ADD_ADDR are now sent sooner multipath-tcp/packetdrill#34

Merged

dcaratti closed this as completed in multipath-tcp/packetdrill#34 Jan 27, 2021

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Packetdrill: ADD_ADDR are now sent sooner #144

Packetdrill: ADD_ADDR are now sent sooner #144

matttbe commented Jan 23, 2021

Packetdrill: ADD_ADDR are now sent sooner #144

Packetdrill: ADD_ADDR are now sent sooner #144

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matttbe commented Jan 23, 2021