linux/drivers/char/ipmi, branch v5.0

ipmi: Don't initialize anything in the core until something uses it

2019-01-23T17:09:32Z

The IPMI driver was recently modified to use SRCU, but it turns out this uses a chunk of percpu memory, even if IPMI is never used. So modify thing to on initialize on the first use. There was already code to sort of handle this for handling init races, so piggy back on top of that, and simplify it in the process. Signed-off-by: Corey Minyard Reported-by: Tejun Heo Cc: Paul E. McKenney Reviewed-by: Paul E. McKenney Cc: stable@vger.kernel.org # 4.18

ipmi: fix use-after-free of user->release_barrier.rda

2019-01-23T16:44:23Z

When we do the following test, we got oops in ipmi_msghandler driver while((1)) do service ipmievd restart & service ipmievd restart done --------------------------------------------------------------- [ 294.230186] Unable to handle kernel paging request at virtual address 0000803fea6ea008 [ 294.230188] Mem abort info: [ 294.230190] ESR = 0x96000004 [ 294.230191] Exception class = DABT (current EL), IL = 32 bits [ 294.230193] SET = 0, FnV = 0 [ 294.230194] EA = 0, S1PTW = 0 [ 294.230195] Data abort info: [ 294.230196] ISV = 0, ISS = 0x00000004 [ 294.230197] CM = 0, WnR = 0 [ 294.230199] user pgtable: 4k pages, 48-bit VAs, pgdp = 00000000a1c1b75a [ 294.230201] [0000803fea6ea008] pgd=0000000000000000 [ 294.230204] Internal error: Oops: 96000004 [#1] SMP [ 294.235211] Modules linked in: nls_utf8 isofs rpcrdma ib_iser ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib rdma_ucm ib_umad rdma_cm ib_cm iw_cm dm_mirror dm_region_hash dm_log dm_mod aes_ce_blk crypto_simd cryptd aes_ce_cipher ghash_ce sha2_ce ses sha256_arm64 sha1_ce hibmc_drm hisi_sas_v2_hw enclosure sg hisi_sas_main sbsa_gwdt ip_tables mlx5_ib ib_uverbs marvell ib_core mlx5_core ixgbe ipmi_si mdio hns_dsaf ipmi_devintf ipmi_msghandler hns_enet_drv hns_mdio [ 294.277745] CPU: 3 PID: 0 Comm: swapper/3 Kdump: loaded Not tainted 5.0.0-rc2+ #113 [ 294.285511] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.37 11/21/2017 [ 294.292835] pstate: 80000005 (Nzcv daif -PAN -UAO) [ 294.297695] pc : __srcu_read_lock+0x38/0x58 [ 294.301940] lr : acquire_ipmi_user+0x2c/0x70 [ipmi_msghandler] [ 294.307853] sp : ffff00001001bc80 [ 294.311208] x29: ffff00001001bc80 x28: ffff0000117e5000 [ 294.316594] x27: 0000000000000000 x26: dead000000000100 [ 294.321980] x25: dead000000000200 x24: ffff803f6bd06800 [ 294.327366] x23: 0000000000000000 x22: 0000000000000000 [ 294.332752] x21: ffff00001001bd04 x20: ffff80df33d19018 [ 294.338137] x19: ffff80df33d19018 x18: 0000000000000000 [ 294.343523] x17: 0000000000000000 x16: 0000000000000000 [ 294.348908] x15: 0000000000000000 x14: 0000000000000002 [ 294.354293] x13: 0000000000000000 x12: 0000000000000000 [ 294.359679] x11: 0000000000000000 x10: 0000000000100000 [ 294.365065] x9 : 0000000000000000 x8 : 0000000000000004 [ 294.370451] x7 : 0000000000000000 x6 : ffff80df34558678 [ 294.375836] x5 : 000000000000000c x4 : 0000000000000000 [ 294.381221] x3 : 0000000000000001 x2 : 0000803fea6ea000 [ 294.386607] x1 : 0000803fea6ea008 x0 : 0000000000000001 [ 294.391994] Process swapper/3 (pid: 0, stack limit = 0x0000000083087293) [ 294.398791] Call trace: [ 294.401266] __srcu_read_lock+0x38/0x58 [ 294.405154] acquire_ipmi_user+0x2c/0x70 [ipmi_msghandler] [ 294.410716] deliver_response+0x80/0xf8 [ipmi_msghandler] [ 294.416189] deliver_local_response+0x28/0x68 [ipmi_msghandler] [ 294.422193] handle_one_recv_msg+0x158/0xcf8 [ipmi_msghandler] [ 294.432050] handle_new_recv_msgs+0xc0/0x210 [ipmi_msghandler] [ 294.441984] smi_recv_tasklet+0x8c/0x158 [ipmi_msghandler] [ 294.451618] tasklet_action_common.isra.5+0x88/0x138 [ 294.460661] tasklet_action+0x2c/0x38 [ 294.468191] __do_softirq+0x120/0x2f8 [ 294.475561] irq_exit+0x134/0x140 [ 294.482445] __handle_domain_irq+0x6c/0xc0 [ 294.489954] gic_handle_irq+0xb8/0x178 [ 294.497037] el1_irq+0xb0/0x140 [ 294.503381] arch_cpu_idle+0x34/0x1a8 [ 294.510096] do_idle+0x1d4/0x290 [ 294.516322] cpu_startup_entry+0x28/0x30 [ 294.523230] secondary_start_kernel+0x184/0x1d0 [ 294.530657] Code: d538d082 d2800023 8b010c81 8b020021 (c85f7c25) [ 294.539746] ---[ end trace 8a7a880dee570b29 ]--- [ 294.547341] Kernel panic - not syncing: Fatal exception in interrupt [ 294.556837] SMP: stopping secondary CPUs [ 294.563996] Kernel Offset: disabled [ 294.570515] CPU features: 0x002,21006008 [ 294.577638] Memory Limit: none [ 294.587178] Starting crashdump kernel... [ 294.594314] Bye! Because the user->release_barrier.rda is freed in ipmi_destroy_user(), but the refcount is not zero, when acquire_ipmi_user() uses user->release_barrier.rda in __srcu_read_lock(), it causes oops. Fix this by calling cleanup_srcu_struct() when the refcount is zero. Fixes: e86ee2d44b44 ("ipmi: Rework locking and shutdown for hot remove") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Yang Yingliang Signed-off-by: Corey Minyard

ipmi: Prevent use-after-free in deliver_response

2019-01-23T16:44:45Z

Some IPMI modules (e.g. ibmpex_msg_handler()) will have ipmi_usr_hdlr handlers that call ipmi_free_recv_msg() directly. This will essentially kfree(msg), leading to use-after-free. This does not happen in the ipmi_devintf module, which will queue the message and run ipmi_free_recv_msg() later. BUG: KASAN: use-after-free in deliver_response+0x12f/0x1b0 Read of size 8 at addr ffff888a7bf20018 by task ksoftirqd/3/27 CPU: 3 PID: 27 Comm: ksoftirqd/3 Tainted: G O 4.19.11-amd64-ani99-debug #12.0.1.601133+pv Hardware name: AppNeta r1000/X11SPW-TF, BIOS 2.1a-AP 09/17/2018 Call Trace: dump_stack+0x92/0xeb print_address_description+0x73/0x290 kasan_report+0x258/0x380 deliver_response+0x12f/0x1b0 ? ipmi_free_recv_msg+0x50/0x50 deliver_local_response+0xe/0x50 handle_one_recv_msg+0x37a/0x21d0 handle_new_recv_msgs+0x1ce/0x440 ... Allocated by task 9885: kasan_kmalloc+0xa0/0xd0 kmem_cache_alloc_trace+0x116/0x290 ipmi_alloc_recv_msg+0x28/0x70 i_ipmi_request+0xb4a/0x1640 ipmi_request_settime+0x1b8/0x1e0 ... Freed by task 27: __kasan_slab_free+0x12e/0x180 kfree+0xe9/0x280 deliver_response+0x122/0x1b0 deliver_local_response+0xe/0x50 handle_one_recv_msg+0x37a/0x21d0 handle_new_recv_msgs+0x1ce/0x440 tasklet_action_common.isra.19+0xc4/0x250 __do_softirq+0x11f/0x51f Fixes: e86ee2d44b44 ("ipmi: Rework locking and shutdown for hot remove") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Fred Klassen Signed-off-by: Corey Minyard

ipmi: msghandler: Fix potential Spectre v1 vulnerabilities

2019-01-23T16:44:23Z

channel and addr->channel are indirectly controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. These issues were detected with the help of Smatch: drivers/char/ipmi/ipmi_msghandler.c:1381 ipmi_set_my_address() warn: potential spectre issue 'user->intf->addrinfo' [w] (local cap) drivers/char/ipmi/ipmi_msghandler.c:1401 ipmi_get_my_address() warn: potential spectre issue 'user->intf->addrinfo' [r] (local cap) drivers/char/ipmi/ipmi_msghandler.c:1421 ipmi_set_my_LUN() warn: potential spectre issue 'user->intf->addrinfo' [w] (local cap) drivers/char/ipmi/ipmi_msghandler.c:1441 ipmi_get_my_LUN() warn: potential spectre issue 'user->intf->addrinfo' [r] (local cap) drivers/char/ipmi/ipmi_msghandler.c:2260 check_addr() warn: potential spectre issue 'intf->addrinfo' [r] (local cap) Fix this by sanitizing channel and addr->channel before using them to index user->intf->addrinfo and intf->addrinfo, correspondingly. Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://lore.kernel.org/lkml/20180423164740.GY17484@dhcp22.suse.cz/ Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Signed-off-by: Corey Minyard

ipmi:ssif: Fix handling of multi-part return messages

2019-01-23T16:44:23Z

The block number was not being compared right, it was off by one when checking the response. Some statistics wouldn't be incremented properly in some cases. Check to see if that middle-part messages always have 31 bytes of data. Signed-off-by: Corey Minyard Cc: stable@vger.kernel.org # 4.4

drivers/ipmi: Replace synchronize_sched() with synchronize_rcu()

2018-11-27T17:21:36Z

Now that synchronize_rcu() waits for preempt-disable regions of code as well as RCU read-side critical sections, synchronize_sched() can be replaced by synchronize_rcu(). This commit therefore makes this change. Signed-off-by: Paul E. McKenney Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: Acked-by: Corey Minyard

ipmi: Fix timer race with module unload

2018-10-12T01:08:27Z

Please note that below oops is from an older kernel, but the same race seems to be present in the upstream kernel too. ---8<--- The following panic was encountered during removing the ipmi_ssif module: [ 526.352555] Unable to handle kernel paging request at virtual address ffff000006923090 [ 526.360464] Mem abort info: [ 526.363257] ESR = 0x86000007 [ 526.366304] Exception class = IABT (current EL), IL = 32 bits [ 526.372221] SET = 0, FnV = 0 [ 526.375269] EA = 0, S1PTW = 0 [ 526.378405] swapper pgtable: 4k pages, 48-bit VAs, pgd = 000000008ae60416 [ 526.385185] [ffff000006923090] *pgd=000000bffcffe803, *pud=000000bffcffd803, *pmd=0000009f4731a003, *pte=0000000000000000 [ 526.396141] Internal error: Oops: 86000007 [#1] SMP [ 526.401008] Modules linked in: nls_iso8859_1 ipmi_devintf joydev input_leds ipmi_msghandler shpchp sch_fq_codel ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear i2c_smbus hid_generic usbhid uas hid usb_storage ast aes_ce_blk i2c_algo_bit aes_ce_cipher qede ttm crc32_ce ptp crct10dif_ce drm_kms_helper ghash_ce syscopyarea sha2_ce sysfillrect sysimgblt pps_core fb_sys_fops sha256_arm64 sha1_ce mpt3sas qed drm raid_class ahci scsi_transport_sas libahci gpio_xlp i2c_xlp9xx aes_neon_bs aes_neon_blk crypto_simd cryptd aes_arm64 [last unloaded: ipmi_ssif] [ 526.468085] CPU: 125 PID: 0 Comm: swapper/125 Not tainted 4.15.0-35-generic #38~lp1775396+build.1 [ 526.476942] Hardware name: To be filled by O.E.M. Saber/Saber, BIOS 0ACKL022 08/14/2018 [ 526.484932] pstate: 00400009 (nzcv daif +PAN -UAO) [ 526.489713] pc : 0xffff000006923090 [ 526.493198] lr : call_timer_fn+0x34/0x178 [ 526.497194] sp : ffff000009b0bdd0 [ 526.500496] x29: ffff000009b0bdd0 x28: 0000000000000082 [ 526.505796] x27: 0000000000000002 x26: ffff000009515188 [ 526.511096] x25: ffff000009515180 x24: ffff0000090f1018 [ 526.516396] x23: ffff000009519660 x22: dead000000000200 [ 526.521696] x21: ffff000006923090 x20: 0000000000000100 [ 526.526995] x19: ffff809eeb466a40 x18: 0000000000000000 [ 526.532295] x17: 000000000000000e x16: 0000000000000007 [ 526.537594] x15: 0000000000000000 x14: 071c71c71c71c71c [ 526.542894] x13: 0000000000000000 x12: 0000000000000000 [ 526.548193] x11: 0000000000000001 x10: ffff000009b0be88 [ 526.553493] x9 : 0000000000000000 x8 : 0000000000000005 [ 526.558793] x7 : ffff80befc1f8528 x6 : 0000000000000020 [ 526.564092] x5 : 0000000000000040 x4 : 0000000020001b20 [ 526.569392] x3 : 0000000000000000 x2 : ffff809eeb466a40 [ 526.574692] x1 : ffff000006923090 x0 : ffff809eeb466a40 [ 526.579992] Process swapper/125 (pid: 0, stack limit = 0x000000002eb50acc) [ 526.586854] Call trace: [ 526.589289] 0xffff000006923090 [ 526.592419] expire_timers+0xc8/0x130 [ 526.596070] run_timer_softirq+0xec/0x1b0 [ 526.600070] __do_softirq+0x134/0x328 [ 526.603726] irq_exit+0xc8/0xe0 [ 526.606857] __handle_domain_irq+0x6c/0xc0 [ 526.610941] gic_handle_irq+0x84/0x188 [ 526.614679] el1_irq+0xe8/0x180 [ 526.617822] cpuidle_enter_state+0xa0/0x328 [ 526.621993] cpuidle_enter+0x34/0x48 [ 526.625564] call_cpuidle+0x44/0x70 [ 526.629040] do_idle+0x1b8/0x1f0 [ 526.632256] cpu_startup_entry+0x2c/0x30 [ 526.636174] secondary_start_kernel+0x11c/0x130 [ 526.640694] Code: bad PC value [ 526.643800] ---[ end trace d020b0b8417c2498 ]--- [ 526.648404] Kernel panic - not syncing: Fatal exception in interrupt [ 526.654778] SMP: stopping secondary CPUs [ 526.658734] Kernel Offset: disabled [ 526.662211] CPU features: 0x5800c38 [ 526.665688] Memory Limit: none [ 526.668768] ---[ end Kernel panic - not syncing: Fatal exception in interrupt Prevent mod_timer from arming a timer that was already removed by del_timer during module unload. Signed-off-by: Jan Glauber Cc: # 3.19 Signed-off-by: Corey Minyard

ipmi:ssif: Add support for multi-part transmit messages > 2 parts

2018-09-18T21:18:44Z

The spec was fairly confusing about how multi-part transmit messages worked, so the original implementation only added support for two part messages. But after talking about it with others and finding something I missed, I think it makes more sense. The spec mentions smbus command 8 in a table at the end of the section on SSIF support as the end transaction. If that works, then all is good and as it should be. However, some implementations seem to use a middle transaction <32 bytes tomark the end because of the confusion in the spec, even though that is an SMBus violation if the number of bytes is zero. So this change adds some tests, if command=8 works, it uses that, otherwise if an empty end transaction works, it uses a middle transaction <32 bytes to mark the end. If neither works, then it limits the size to 63 bytes as it is now. Cc: Harri Hakkarainen Cc: Bazhenov, Dmitry Cc: Mach, Dat Signed-off-by: Corey Minyard

ipmi: Remove platform driver overrides and use the id_table

2018-09-18T21:15:33Z

The IPMI DMI code was adding platform overrides, which is not really an ideal solution. Switch to using the id_table in the drivers to identify the devices. Signed-off-by: Corey Minyard

ipmi: Free the address list on module cleanup

2018-09-18T21:15:33Z

Otherwise the memory is leaked. Signed-off-by: Corey Minyard