- 31 Jan, 2019 40 commits
-
-
Daniel Borkmann authored
[ commit d3bd7413 upstream ] While 979d63d5 ("bpf: prevent out of bounds speculation on pointer arithmetic") took care of rejecting alu op on pointer when e.g. pointer came from two different map values with different map properties such as value size, Jann reported that a case was not covered yet when a given alu op is used in both "ptr_reg += reg" and "numeric_reg += reg" from different branches where we would incorrectly try to sanitize based on the pointer's limit. Catch this corner case and reject the program instead. Fixes: 979d63d5 ("bpf: prevent out of bounds speculation on pointer arithmetic") Reported-by:
Jann Horn <jannh@google.com> Signed-off-by:
Daniel Borkmann <daniel@iogearbox.net> Acked-by:
Alexei Starovoitov <ast@kernel.org> Signed-off-by:
Sasha Levin <sashal@kernel.org>
-
Daniel Borkmann authored
[ commit 979d63d5 upstream ] Jann reported that the original commit back in b2157399 ("bpf: prevent out-of-bounds speculation") was not sufficient to stop CPU from speculating out of bounds memory access: While b2157399 only focussed on masking array map access for unprivileged users for tail calls and data access such that the user provided index gets sanitized from BPF program and syscall side, there is still a more generic form affected from BPF programs that applies to most maps that hold user data in relation to dynamic map access when dealing with unknown scalars or "slow" known scalars as access offset, for example: - Load a map value pointer into R6 - Load an index into R7 - Do a slow computation (e.g. with a memory dependency) that loads a limit into R8 (e.g. load the limit from a map for high latency, then mask it to make the verifier happy) - Exit if R7 >= R8 (mispredicted branch) - Load R0 = R6[R7] - Load R0 = R6[R0] For unknown scalars there are two options in the BPF verifier where we could derive knowledge from in order to guarantee safe access to the memory: i) While </>/<=/>= variants won't allow to derive any lower or upper bounds from the unknown scalar where it would be safe to add it to the map value pointer, it is possible through ==/!= test however. ii) another option is to transform the unknown scalar into a known scalar, for example, through ALU ops combination such as R &= <imm> followed by R |= <imm> or any similar combination where the original information from the unknown scalar would be destroyed entirely leaving R with a constant. The initial slow load still precedes the latter ALU ops on that register, so the CPU executes speculatively from that point. Once we have the known scalar, any compare operation would work then. A third option only involving registers with known scalars could be crafted as described in [0] where a CPU port (e.g. Slow Int unit) would be filled with many dependent computations such that the subsequent condition depending on its outcome has to wait for evaluation on its execution port and thereby executing speculatively if the speculated code can be scheduled on a different execution port, or any other form of mistraining as described in [1], for example. Given this is not limited to only unknown scalars, not only map but also stack access is affected since both is accessible for unprivileged users and could potentially be used for out of bounds access under speculation. In order to prevent any of these cases, the verifier is now sanitizing pointer arithmetic on the offset such that any out of bounds speculation would be masked in a way where the pointer arithmetic result in the destination register will stay unchanged, meaning offset masked into zero similar as in array_index_nospec() case. With regards to implementation, there are three options that were considered: i) new insn for sanitation, ii) push/pop insn and sanitation as inlined BPF, iii) reuse of ax register and sanitation as inlined BPF. Option i) has the downside that we end up using from reserved bits in the opcode space, but also that we would require each JIT to emit masking as native arch opcodes meaning mitigation would have slow adoption till everyone implements it eventually which is counter-productive. Option ii) and iii) have both in common that a temporary register is needed in order to implement the sanitation as inlined BPF since we are not allowed to modify the source register. While a push / pop insn in ii) would be useful to have in any case, it requires once again that every JIT needs to implement it first. While possible, amount of changes needed would also be unsuitable for a -stable patch. Therefore, the path which has fewer changes, less BPF instructions for the mitigation and does not require anything to be changed in the JITs is option iii) which this work is pursuing. The ax register is already mapped to a register in all JITs (modulo arm32 where it's mapped to stack as various other BPF registers there) and used in constant blinding for JITs-only so far. It can be reused for verifier rewrites under certain constraints. The interpreter's tmp "register" has therefore been remapped into extending the register set with hidden ax register and reusing that for a number of instructions that needed the prior temporary variable internally (e.g. div, mod). This allows for zero increase in stack space usage in the interpreter, and enables (restricted) generic use in rewrites otherwise as long as such a patchlet does not make use of these instructions. The sanitation mask is dynamic and relative to the offset the map value or stack pointer currently holds. There are various cases that need to be taken under consideration for the masking, e.g. such operation could look as follows: ptr += val or val += ptr or ptr -= val. Thus, the value to be sanitized could reside either in source or in destination register, and the limit is different depending on whether the ALU op is addition or subtraction and depending on the current known and bounded offset. The limit is derived as follows: limit := max_value_size - (smin_value + off). For subtraction: limit := umax_value + off. This holds because we do not allow any pointer arithmetic that would temporarily go out of bounds or would have an unknown value with mixed signed bounds where it is unclear at verification time whether the actual runtime value would be either negative or positive. For example, we have a derived map pointer value with constant offset and bounded one, so limit based on smin_value works because the verifier requires that statically analyzed arithmetic on the pointer must be in bounds, and thus it checks if resulting smin_value + off and umax_value + off is still within map value bounds at time of arithmetic in addition to time of access. Similarly, for the case of stack access we derive the limit as follows: MAX_BPF_STACK + off for subtraction and -off for the case of addition where off := ptr_reg->off + ptr_reg->var_off.value. Subtraction is a special case for the masking which can be in form of ptr += -val, ptr -= -val, or ptr -= val. In the first two cases where we know that the value is negative, we need to temporarily negate the value in order to do the sanitation on a positive value where we later swap the ALU op, and restore original source register if the value was in source. The sanitation of pointer arithmetic alone is still not fully sufficient as is, since a scenario like the following could happen ... PTR += 0x1000 (e.g. K-based imm) PTR -= BIG_NUMBER_WITH_SLOW_COMPARISON PTR += 0x1000 PTR -= BIG_NUMBER_WITH_SLOW_COMPARISON [...] ... which under speculation could end up as ... PTR += 0x1000 PTR -= 0 [ truncated by mitigation ] PTR += 0x1000 PTR -= 0 [ truncated by mitigation ] [...] ... and therefore still access out of bounds. To prevent such case, the verifier is also analyzing safety for potential out of bounds access under speculative execution. Meaning, it is also simulating pointer access under truncation. We therefore "branch off" and push the current verification state after the ALU operation with known 0 to the verification stack for later analysis. Given the current path analysis succeeded it is likely that the one under speculation can be pruned. In any case, it is also subject to existing complexity limits and therefore anything beyond this point will be rejected. In terms of pruning, it needs to be ensured that the verification state from speculative execution simulation must never prune a non-speculative execution path, therefore, we mark verifier state accordingly at the time of push_stack(). If verifier detects out of bounds access under speculative execution from one of the possible paths that includes a truncation, it will reject such program. Given we mask every reg-based pointer arithmetic for unprivileged programs, we've been looking into how it could affect real-world programs in terms of size increase. As the majority of programs are targeted for privileged-only use case, we've unconditionally enabled masking (with its alu restrictions on top of it) for privileged programs for the sake of testing in order to check i) whether they get rejected in its current form, and ii) by how much the number of instructions and size will increase. We've tested this by using Katran, Cilium and test_l4lb from the kernel selftests. For Katran we've evaluated balancer_kern.o, Cilium bpf_lxc.o and an older test object bpf_lxc_opt_-DUNKNOWN.o and l4lb we've used test_l4lb.o as well as test_l4lb_noinline.o. We found that none of the programs got rejected by the verifier with this change, and that impact is rather minimal to none. balancer_kern.o had 13,904 bytes (1,738 insns) xlated and 7,797 bytes JITed before and after the change. Most complex program in bpf_lxc.o had 30,544 bytes (3,817 insns) xlated and 18,538 bytes JITed before and after and none of the other tail call programs in bpf_lxc.o had any changes either. For the older bpf_lxc_opt_-DUNKNOWN.o object we found a small increase from 20,616 bytes (2,576 insns) and 12,536 bytes JITed before to 20,664 bytes (2,582 insns) and 12,558 bytes JITed after the change. Other programs from that object file had similar small increase. Both test_l4lb.o had no change and remained at 6,544 bytes (817 insns) xlated and 3,401 bytes JITed and for test_l4lb_noinline.o constant at 5,080 bytes (634 insns) xlated and 3,313 bytes JITed. This can be explained in that LLVM typically optimizes stack based pointer arithmetic by using K-based operations and that use of dynamic map access is not overly frequent. However, in future we may decide to optimize the algorithm further under known guarantees from branch and value speculation. Latter seems also unclear in terms of prediction heuristics that today's CPUs apply as well as whether there could be collisions in e.g. the predictor's Value History/Pattern Table for triggering out of bounds access, thus masking is performed unconditionally at this point but could be subject to relaxation later on. We were generally also brainstorming various other approaches for mitigation, but the blocker was always lack of available registers at runtime and/or overhead for runtime tracking of limits belonging to a specific pointer. Thus, we found this to be minimally intrusive under given constraints. With that in place, a simple example with sanitized access on unprivileged load at post-verification time looks as follows: # bpftool prog dump xlated id 282 [...] 28: (79) r1 = *(u64 *)(r7 +0) 29: (79) r2 = *(u64 *)(r7 +8) 30: (57) r1 &= 15 31: (79) r3 = *(u64 *)(r0 +4608) 32: (57) r3 &= 1 33: (47) r3 |= 1 34: (2d) if r2 > r3 goto pc+19 35: (b4) (u32) r11 = (u32) 20479 | 36: (1f) r11 -= r2 | Dynamic sanitation for pointer 37: (4f) r11 |= r2 | arithmetic with registers 38: (87) r11 = -r11 | containing bounded or known 39: (c7) r11 s>>= 63 | scalars in order to prevent 40: (5f) r11 &= r2 | out of bounds speculation. 41: (0f) r4 += r11 | 42: (71) r4 = *(u8 *)(r4 +0) 43: (6f) r4 <<= r1 [...] For the case where the scalar sits in the destination register as opposed to the source register, the following code is emitted for the above example: [...] 16: (b4) (u32) r11 = (u32) 20479 17: (1f) r11 -= r2 18: (4f) r11 |= r2 19: (87) r11 = -r11 20: (c7) r11 s>>= 63 21: (5f) r2 &= r11 22: (0f) r2 += r0 23: (61) r0 = *(u32 *)(r2 +0) [...] JIT blinding example with non-conflicting use of r10: [...] d5: je 0x0000000000000106 _ d7: mov 0x0(%rax),%edi | da: mov $0xf153246,%r10d | Index load from map value and e0: xor $0xf153259,%r10 | (const blinded) mask with 0x1f. e7: and %r10,%rdi |_ ea: mov $0x2f,%r10d | f0: sub %rdi,%r10 | Sanitized addition. Both use r10 f3: or %rdi,%r10 | but do not interfere with each f6: neg %r10 | other. (Neither do these instructions f9: sar $0x3f,%r10 | interfere with the use of ax as temp fd: and %r10,%rdi | in interpreter.) 100: add %rax,%rdi |_ 103: mov 0x0(%rdi),%eax [...] Tested that it fixes Jann's reproducer, and also checked that test_verifier and test_progs suite with interpreter, JIT and JIT with hardening enabled on x86-64 and arm64 runs successfully. [0] Speculose: Analyzing the Security Implications of Speculative Execution in CPUs, Giorgi Maisuradze and Christian Rossow, https://arxiv.org/pdf/1801.04084.pdf [1] A Systematic Evaluation of Transient Execution Attacks and Defenses, Claudio Canella, Jo Van Bulck, Michael Schwarz, Moritz Lipp, Benjamin von Berg, Philipp Ortner, Frank Piessens, Dmitry Evtyushkin, Daniel Gruss, https://arxiv.org/pdf/1811.05441.pdf Fixes: b2157399 ("bpf: prevent out-of-bounds speculation") Reported-by:
-
Daniel Borkmann authored
[ commit b7137c4e upstream ] In check_map_access() we probe actual bounds through __check_map_access() with offset of reg->smin_value + off for lower bound and offset of reg->umax_value + off for the upper bound. However, even though the reg->smin_value could have a negative value, the final result of the sum with off could be positive when pointer arithmetic with known and unknown scalars is combined. In this case we reject the program with an error such as "R<x> min value is negative, either use unsigned index or do a if (index >=0) check." even though the access itself would be fine. Therefore extend the check to probe whether the actual resulting reg->smin_value + off is less than zero. Signed-off-by:
-
Daniel Borkmann authored
[ commit 9d7eceed upstream ] For unknown scalars of mixed signed bounds, meaning their smin_value is negative and their smax_value is positive, we need to reject arithmetic with pointer to map value. For unprivileged the goal is to mask every map pointer arithmetic and this cannot reliably be done when it is unknown at verification time whether the scalar value is negative or positive. Given this is a corner case, the likelihood of breaking should be very small. Signed-off-by:
-
Daniel Borkmann authored
[ commit e4298d25 upstream ] Restrict stack pointer arithmetic for unprivileged users in that arithmetic itself must not go out of bounds as opposed to the actual access later on. Therefore after each adjust_ptr_min_max_vals() with a stack pointer as a destination we simulate a check_stack_access() of 1 byte on the destination and once that fails the program is rejected for unprivileged program loads. This is analog to map value pointer arithmetic and needed for masking later on. Signed-off-by:
-
Daniel Borkmann authored
[ commit 0d6303db upstream ] Restrict map value pointer arithmetic for unprivileged users in that arithmetic itself must not go out of bounds as opposed to the actual access later on. Therefore after each adjust_ptr_min_max_vals() with a map value pointer as a destination it will simulate a check_map_access() of 1 byte on the destination and once that fails the program is rejected for unprivileged program loads. We use this later on for masking any pointer arithmetic with the remainder of the map value space. The likelihood of breaking any existing real-world unprivileged eBPF program is very small for this corner case. Signed-off-by:
-
Daniel Borkmann authored
[ commit 9b73bfdd upstream ] Right now we are using BPF ax register in JIT for constant blinding as well as in interpreter as temporary variable. Verifier will not be able to use it simply because its use will get overridden from the former in bpf_jit_blind_insn(). However, it can be made to work in that blinding will be skipped if there is prior use in either source or destination register on the instruction. Taking constraints of ax into account, the verifier is then open to use it in rewrites under some constraints. Note, ax register already has mappings in every eBPF JIT. Signed-off-by:
-
Daniel Borkmann authored
[ commit 144cd91c upstream ] This change moves the on-stack 64 bit tmp variable in ___bpf_prog_run() into the hidden ax register. The latter is currently only used in JITs for constant blinding as a temporary scratch register, meaning the BPF interpreter will never see the use of ax. Therefore it is safe to use it for the cases where tmp has been used earlier. This is needed to later on allow restricted hidden use of ax in both interpreter and JITs. Signed-off-by:
-
Daniel Borkmann authored
[ commit c08435ec upstream ] Move prev_insn_idx and insn_idx from the do_check() function into the verifier environment, so they can be read inside the various helper functions for handling the instructions. It's easier to put this into the environment rather than changing all call-sites only to pass it along. insn_idx is useful in particular since this later on allows to hold state in env->insn_aux_data[env->insn_idx]. Signed-off-by:
-
Alexei Starovoitov authored
[ commit ceefbc96 upstream ] malicious bpf program may try to force the verifier to remember a lot of distinct verifier states. Put a limit to number of per-insn 'struct bpf_verifier_state'. Note that hitting the limit doesn't reject the program. It potentially makes the verifier do more steps to analyze the program. It means that malicious programs will hit BPF_COMPLEXITY_LIMIT_INSNS sooner instead of spending cpu time walking long link list. The limit of BPF_COMPLEXITY_LIMIT_STATES==64 affects cilium progs with slight increase in number of "steps" it takes to successfully verify the programs: before after bpf_lb-DLB_L3.o 1940 1940 bpf_lb-DLB_L4.o 3089 3089 bpf_lb-DUNKNOWN.o 1065 1065 bpf_lxc-DDROP_ALL.o 28052 | 28162 bpf_lxc-DUNKNOWN.o 35487 | 35541 bpf_netdev.o 10864 10864 bpf_overlay.o 6643 6643 bpf_lcx_jit.o 38437 38437 But it also makes malicious program to be rejected in 0.4 seconds vs 6.5 Hence apply this limit to unprivileged programs only. Signed-off-by:
Edward Cree <ecree@solarflare.com> Signed-off-by:
-
Alexei Starovoitov authored
[ commit 4f7b3e82 upstream ] pathological bpf programs may try to force verifier to explode in the number of branch states: 20: (d5) if r1 s<= 0x24000028 goto pc+0 21: (b5) if r0 <= 0xe1fa20 goto pc+2 22: (d5) if r1 s<= 0x7e goto pc+0 23: (b5) if r0 <= 0xe880e000 goto pc+0 24: (c5) if r0 s< 0x2100ecf4 goto pc+0 25: (d5) if r1 s<= 0xe880e000 goto pc+1 26: (c5) if r0 s< 0xf4041810 goto pc+0 27: (d5) if r1 s<= 0x1e007e goto pc+0 28: (b5) if r0 <= 0xe86be000 goto pc+0 29: (07) r0 += 16614 30: (c5) if r0 s< 0x6d0020da goto pc+0 31: (35) if r0 >= 0x2100ecf4 goto pc+0 Teach verifier to recognize always taken and always not taken branches. This analysis is already done for == and != comparison. Expand it to all other branches. It also helps real bpf programs to be verified faster: before after bpf_lb-DLB_L3.o 2003 1940 bpf_lb-DLB_L4.o 3173 3089 bpf_lb-DUNKNOWN.o 1080 1065 bpf_lxc-DDROP_ALL.o 29584 28052 bpf_lxc-DUNKNOWN.o 36916 35487 bpf_netdev.o 11188 10864 bpf_overlay.o 6679 6643 bpf_lcx_jit.o 39555 38437 Reported-by:
Anatoly Trosinenko <anatoly.trosinenko@gmail.com> Signed-off-by:
-
Neil Armstrong authored
commit ce0210c1 upstream. Since commit 2bcd3eca when switching mode from X11 (ubuntu mate for example) the display gets blurry, looking like an invalid framebuffer width. This commit fixed atomic crtc modesetting in a totally wrong way and introduced a local unnecessary ->enabled crtc state. This commit reverts the crctc _begin() and _enable() changes and simply adds drm_atomic_helper_commit_tail_rpm as helper. Reported-by:
Tony McKahan <tonymckahan@gmail.com> Suggested-by:
Daniel Vetter <daniel@ffwll.ch> Fixes: 2bcd3eca ("drm/meson: Fixes for drm_crtc_vblank_on/off support") Signed-off-by:
Neil Armstrong <narmstrong@baylibre.com> Acked-by:
Daniel Vetter <daniel.vetter@ffwll.ch> [narmstrong: fixed blank line issue from checkpatch] Link: https://patchwork.freedesktop.org/patch/msgid/20190114153118.8024-1-narmstrong@baylibre.comSigned-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Nicolas Pitre authored
commit 0c9b1965 upstream. User space using poll() on /dev/vcs devices are not awaken when a screen size change occurs. Let's fix that. Signed-off-by:
Nicolas Pitre <nico@linaro.org> Cc: stable <stable@vger.kernel.org> Signed-off-by:
-
Nicolas Pitre authored
commit 7e1d2263 upstream. Every invocation of notify_write() and notify_update() is performed under the console lock, except for one case. Let's fix that. Signed-off-by:
-
Nicolas Pitre authored
commit 6609cff6 upstream. When kernel messages are printed to the console, they appear blank on the unicode screen. This is because vt_console_print() is lacking a call to vc_uniscr_putc(). However the later function assumes vc->vc_x is always up to date when called, which is not the case here as vt_console_print() uses it to mark the beginning of the display update. This patch reworks (and simplifies) vt_console_print() so that vc->vc_x is always valid and keeps the start of display update in a local variable instead, which finally allows for adding the missing vc_uniscr_putc() call. Signed-off-by:
-
Uwe Kleine-König authored
commit a55234da upstream. Commit cbffaf7a ("can: flexcan: Always use last mailbox for TX") introduced a loop letting i run up to (including) ARRAY_SIZE(regs->mb) and in the body accessed regs->mb[i] which is an out-of-bounds array access that then resulted in an access to an reserved register area. Later this was changed by commit 0517961c ("can: flexcan: Add provision for variable payload size") to iterate a bit differently but still runs one iteration too much resulting to call flexcan_get_mb(priv, priv->mb_count) which results in a WARN_ON and then a NULL pointer exception. This only affects devices compatible with "fsl,p1010-flexcan", "fsl,imx53-flexcan", "fsl,imx35-flexcan", "fsl,imx25-flexcan", "fsl,imx28-flexcan", so newer i.MX SoCs are not affected. Fixes: cbffaf7a ("can: flexcan: Always use last mailbox for TX") Signed-off-by:
Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: linux-stable <stable@vger.kernel.org> # >= 4.20 Signed-off-by:
Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by:
-
Oliver Hartkopp authored
commit 93171ba6 upstream. Kyungtae Kim detected a potential integer overflow in bcm_[rx|tx]_setup() when the conversion into ktime multiplies the given value with NSEC_PER_USEC (1000). Reference: https://marc.info/?l=linux-can&m=154732118819828&w=2 Add a check for the given tv_usec, so that the value stays below one second. Additionally limit the tv_sec value to a reasonable value for CAN related use-cases of 400 days and ensure all values to be positive. Reported-by:
Kyungtae Kim <kt0755@gmail.com> Tested-by:
Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by:
Andre Naujoks <nautsch2@gmail.com> Signed-off-by:
-
Manfred Schlaegl authored
commit 7b12c818 upstream. This patch revert commit 7da11ba5 ("can: dev: __can_get_echo_skb(): print error message, if trying to echo non existing skb") After introduction of this change we encountered following new error message on various i.MX plattforms (flexcan): | flexcan 53fc8000.can can0: __can_get_echo_skb: BUG! Trying to echo non | existing skb: can_priv::echo_skb[0] The introduction of the message was a mistake because priv->echo_skb[idx] = NULL is a perfectly valid in following case: If CAN_RAW_LOOPBACK is disabled (setsockopt) in applications, the pkt_type of the tx skb's given to can_put_echo_skb is set to PACKET_LOOPBACK. In this case can_put_echo_skb will not set priv->echo_skb[idx]. It is therefore kept NULL. As additional argument for revert: The order of check and usage of idx was changed. idx is used to access an array element before checking it's boundaries. Signed-off-by:
Manfred Schlaegl <manfred.schlaegl@ginzinger.com> Fixes: 7da11ba5 ("can: dev: __can_get_echo_skb(): print error message, if trying to echo non existing skb") Cc: linux-stable <stable@vger.kernel.org> Signed-off-by:
-
Marc Zyngier authored
commit 8208d170 upstream. The way we allocate events works fine in most cases, except when multiple PCI devices share an ITS-visible DevID, and that one of them is trying to use MultiMSI allocation. In that case, our allocation is not guaranteed to be zero-based anymore, and we have to make sure we allocate it on a boundary that is compatible with the PCI Multi-MSI constraints. Fix this by allocating the full region upfront instead of iterating over the number of MSIs. MSI-X are always allocated one by one, so this shouldn't change anything on that front. Fixes: b48ac83d ("irqchip: GICv3: ITS: MSI support") Cc: stable@vger.kernel.org Reported-by:
Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by:
Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:
-
Thomas Gleixner authored
commit 56cb4e50 upstream. The recent addition of SPDX license identifiers to the files in drivers/net/ethernet/sun created a licensing conflict. The cassini driver files contain a proper license notice: * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. but the SPDX change added: SPDX-License-Identifier: GPL-2.0 So the file got tagged GPL v2 only while in fact it is licensed under GPL v2 or later. It's nice that people care about the SPDX tags, but they need to be more careful about it. Not everything under (the) sun belongs to ... Fix up the SPDX identifier and remove the boiler plate text as it is redundant. Fixes: c861ef83 ("sun: Add SPDX license tags to Sun network drivers") Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Cc: Shannon Nelson <shannon.nelson@oracle.com> Cc: Zhu Yanjun <yanjun.zhu@oracle.com> Cc: David S. Miller <davem@davemloft.net> Cc: netdev@vger.kernel.org Cc: stable@vger.kernel.org Acked-by:
Shannon Nelson <shannon.lee.nelson@gmail.com> Reviewed-by:
Zhu Yanjun <yanjun.zhu@oracle.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
-
Thomas Gleixner authored
commit 93ad0fc0 upstream. The recent commit which prevented a division by 0 issue in the alarm timer code broke posix CPU timers as an unwanted side effect. The reason is that the common rearm code checks for timer->it_interval being 0 now. What went unnoticed is that the posix cpu timer setup does not initialize timer->it_interval as it stores the interval in CPU timer specific storage. The reason for the separate storage is historical as the posix CPU timers always had a 64bit nanoseconds representation internally while timer->it_interval is type ktime_t which used to be a modified timespec representation on 32bit machines. Instead of reverting the offending commit and fixing the alarmtimer issue in the alarmtimer code, store the interval in timer->it_interval at CPU timer setup time so the common code check works. This also repairs the existing inconistency of the posix CPU timer code which kept a single shot timer armed despite of the interval being 0. The separate storage can be removed in mainline, but that needs to be a separate commit as the current one has to be backported to stable kernels. Fixes: 0e334db6 ("posix-timers: Fix division by zero bug") Reported-by:
H.J. Lu <hjl.tools@gmail.com> Signed-off-by:
-
Jan Beulich authored
commit fc24d75a upstream. While in the native case entry into the kernel happens on the trampoline stack, PV Xen kernels get entered with the current thread stack right away. Hence source and destination stacks are identical in that case, and special care is needed. Other than in sync_regs() the copying done on the INT80 path isn't NMI / #MC safe, as either of these events occurring in the middle of the stack copying would clobber data on the (source) stack. There is similar code in interrupt_entry() and nmi(), but there is no fixup required because those code paths are unreachable in XEN PV guests. [ tglx: Sanitized subject, changelog, Fixes tag and stable mail address. Sigh ] Fixes: 7f2590a1 ("x86/entry/64: Use a per-CPU trampoline stack for IDT entries") Signed-off-by:
Jan Beulich <jbeulich@suse.com> Signed-off-by:
Juergen Gross <jgross@suse.com> Acked-by:
Andy Lutomirski <luto@kernel.org> Cc: Peter Anvin <hpa@zytor.com> Cc: xen-devel@lists.xenproject.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/5C3E1128020000780020DFAD@prv1-mh.provo.novell.comSigned-off-by:
-
Daniel Drake authored
commit 7e6fc2f5 upstream. The outb() function takes parameters value and port, in that order. Fix the parameters used in the kalsr i8254 fallback code. Fixes: 5bfce5ef ("x86, kaslr: Provide randomness functions") Signed-off-by:
Daniel Drake <drake@endlessm.com> Signed-off-by:
-
Dave Hansen authored
commit e1812933 upstream. There was a bug where the per-mm pkey state was not being preserved across fork() in the child. fork() is performed in the pkey selftests, but all of the pkey activity is performed in the parent. The child does not perform any actions sensitive to pkey state. To make the test more sensitive to these kinds of bugs, add a fork() where the parent exits, and execution continues in the child. To achieve this let the key exhaustion test not terminate at the first allocation failure and fork after 2*NR_PKEYS loops and continue in the child. Signed-off-by:
Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by:
-
Dave Hansen authored
commit a31e184e upstream. Memory protection key behavior should be the same in a child as it was in the parent before a fork. But, there is a bug that resets the state in the child at fork instead of preserving it. The creation of new mm's is a bit convoluted. At fork(), the code does: 1. memcpy() the parent mm to initialize child 2. mm_init() to initalize some select stuff stuff 3. dup_mmap() to create true copies that memcpy() did not do right For pkeys two bits of state need to be preserved across a fork: 'execute_only_pkey' and 'pkey_allocation_map'. Those are preserved by the memcpy(), but mm_init() invokes init_new_context() which overwrites 'execute_only_pkey' and 'pkey_allocation_map' with "new" values. The author of the code erroneously believed that init_new_context is *only* called at execve()-time. But, alas, init_new_context() is used at execve() and fork(). The result is that, after a fork(), the child's pkey state ends up looking like it does after an execve(), which is totally wrong. pkeys that are already allocated can be allocated again, for instance. To fix this, add code called by dup_mmap() to copy the pkey state from parent to child explicitly. Also add a comment above init_new_context() to make it more clear to the next poor sod what this code is used for. Fixes: e8c24d3a ("x86/pkeys: Allocation/free syscalls") Signed-off-by:
-
KarimAllah Ahmed authored
commit 22a7cdca upstream. The spec only requires the posted interrupt descriptor address to be 64-bytes aligned (i.e. bits[0:5] == 0). Using page_address_valid also forces the address to be page aligned. Only validate that the address does not cross the maximum physical address without enforcing a page alignment. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: x86@kernel.org Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Fixes: 6de84e58 ("nVMX x86: check posted-interrupt descriptor addresss on vmentry of L2") Signed-off-by:
KarimAllah Ahmed <karahmed@amazon.de> Reviewed-by:
Jim Mattson <jmattson@google.com> Reviewed-by:
Krish Sadhuhan <krish.sadhukhan@oracle.com> Signed-off-by:
Radim Krčmář <rkrcmar@redhat.com> From: Mark Mielke <mark.mielke@gmail.com> Signed-off-by:
-
Tom Roeder authored
commit 3a33d030 upstream. This changes the allocation of cached_vmcs12 to use kzalloc instead of kmalloc. This removes the information leak found by Syzkaller (see Reported-by) in this case and prevents similar leaks from happening based on cached_vmcs12. It also changes vmx_get_nested_state to copy out the full 4k VMCS12_SIZE in copy_to_user rather than only the size of the struct. Tested: rebuilt against head, booted, and ran the syszkaller repro https://syzkaller.appspot.com/text?tag=ReproC&x=174efca3400000 without observing any problems. Reported-by: syzbot+ded1696f6b50b615b630@syzkaller.appspotmail.com Fixes: 8fcc4b59 Cc: stable@vger.kernel.org Signed-off-by:
Tom Roeder <tmroeder@google.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:
-
Sean Christopherson authored
commit de81c2f9 upstream. KVM hypercalls return a negative value error code in case of a fatal error, e.g. when the hypercall isn't supported or was made with invalid parameters. WARN_ONCE on fatal errors when sending PV IPIs as any such error all but guarantees an SMP system will hang due to a missing IPI. Fixes: aaffcfd1 ("KVM: X86: Implement PV IPIs in linux guest") Cc: stable@vger.kernel.org Cc: Wanpeng Li <wanpengli@tencent.com> Signed-off-by:
Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by:
-
Sean Christopherson authored
commit 1ed199a4 upstream. The recognition of the KVM_HC_SEND_IPI hypercall was unintentionally wrapped in "#ifdef CONFIG_X86_64", causing 32-bit KVM hosts to reject any and all PV IPI requests despite advertising the feature. This results in all KVM paravirtualized guests hanging during SMP boot due to IPIs never being delivered. Fixes: 4180bf1b ("KVM: X86: Implement "send IPI" hypercall") Cc: stable@vger.kernel.org Cc: Wanpeng Li <wanpengli@tencent.com> Signed-off-by:
-
Alexander Popov authored
commit 5cc244a2 upstream. The single-step debugging of KVM guests on x86 is broken: if we run gdb 'stepi' command at the breakpoint when the guest interrupts are enabled, RIP always jumps to native_apic_mem_write(). Then other nasty effects follow. Long investigation showed that on Jun 7, 2017 the commit c8401dda ("KVM: x86: fix singlestepping over syscall") introduced the kvm_run.debug corruption: kvm_vcpu_do_singlestep() can be called without X86_EFLAGS_TF set. Let's fix it. Please consider that for -stable. Signed-off-by:
Alexander Popov <alex.popov@linux.com> Cc: stable@vger.kernel.org Fixes: c8401dda ("KVM: x86: fix singlestepping over syscall") Signed-off-by:
-
Alex Deucher authored
commit f15f3eb2 upstream. Needs ATPX rather than _PR3 for dGPU power control. Bug: https://bugzilla.kernel.org/show_bug.cgi?id=202263Reviewed-by:
Jim Qu <Jim.Qu@amd.com> Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org Signed-off-by:
-
Milan Broz authored
commit 1856b9f7 upstream. The dm-crypt cipher specification in a mapping table is defined as: cipher[:keycount]-chainmode-ivmode[:ivopts] or (new crypt API format): capi:cipher_api_spec-ivmode[:ivopts] For ESSIV, the parameter includes hash specification, for example: aes-cbc-essiv:sha256 The implementation expected that additional IV option to never include another dash '-' character. But, with SHA3, there are names like sha3-256; so the mapping table parser fails: dmsetup create test --table "0 8 crypt aes-cbc-essiv:sha3-256 9c1185a5c5e9fc54612808977ee8f5b9e 0 /dev/sdb 0" or (new crypt API format) dmsetup create test --table "0 8 crypt capi:cbc(aes)-essiv:sha3-256 9c1185a5c5e9fc54612808977ee8f5b9e 0 /dev/sdb 0" device-mapper: crypt: Ignoring unexpected additional cipher options device-mapper: table: 253:0: crypt: Error creating IV device-mapper: ioctl: error adding target to table Fix the dm-crypt constructor to ignore additional dash in IV options and also remove a bogus warning (that is ignored anyway). Cc: stable@vger.kernel.org # 4.12+ Signed-off-by:
Milan Broz <gmazyland@gmail.com> Signed-off-by:
Mike Snitzer <snitzer@redhat.com> Signed-off-by:
-
Joe Thornber authored
commit d445bd9c upstream. Commit 00a0ea33 ("dm thin: do not queue freed thin mapping for next stage processing") changed process_prepared_discard_passdown_pt1() to increment all the blocks being discarded until after the passdown had completed to avoid them being prematurely reused. IO issued to a thin device that breaks sharing with a snapshot, followed by a discard issued to snapshot(s) that previously shared the block(s), results in passdown_double_checking_shared_status() being called to iterate through the blocks double checking their reference count is zero and issuing the passdown if so. So a side effect of commit 00a0ea33 is passdown_double_checking_shared_status() was broken. Fix this by checking if the block reference count is greater than 1. Also, rename dm_pool_block_is_used() to dm_pool_block_is_shared(). Fixes: 00a0ea33 ("dm thin: do not queue freed thin mapping for next stage processing") Cc: stable@vger.kernel.org # 4.9+ Reported-by: ryan.p.norwood@gmail.com Signed-off-by:
Joe Thornber <ejt@redhat.com> Signed-off-by:
-
Marc Gonzalez authored
commit d6724756 upstream. memcpy_fromio() doesn't provide any control over access size. For example, on arm64, it is implemented using readb and readq. This may trigger a synchronous external abort: [ 3.729943] Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP [ 3.737000] Modules linked in: [ 3.744371] CPU: 2 PID: 1 Comm: swapper/0 Tainted: G S 4.20.0-rc4 #16 [ 3.747413] Hardware name: Qualcomm Technologies, Inc. MSM8998 v1 MTP (DT) [ 3.755295] pstate: 00000005 (nzcv daif -PAN -UAO) [ 3.761978] pc : __memcpy_fromio+0x68/0x80 [ 3.766718] lr : ufshcd_dump_regs+0x50/0xb0 [ 3.770767] sp : ffff00000807ba00 [ 3.774830] x29: ffff00000807ba00 x28: 00000000fffffffb [ 3.778344] x27: ffff0000089db068 x26: ffff8000f6e58000 [ 3.783728] x25: 000000000000000e x24: 0000000000000800 [ 3.789023] x23: ffff8000f6e587c8 x22: 0000000000000800 [ 3.794319] x21: ffff000008908368 x20: ffff8000f6e1ab80 [ 3.799615] x19: 000000000000006c x18: ffffffffffffffff [ 3.804910] x17: 0000000000000000 x16: 0000000000000000 [ 3.810206] x15: ffff000009199648 x14: ffff000089244187 [ 3.815502] x13: ffff000009244195 x12: ffff0000091ab000 [ 3.820797] x11: 0000000005f5e0ff x10: ffff0000091998a0 [ 3.826093] x9 : 0000000000000000 x8 : ffff8000f6e1ac00 [ 3.831389] x7 : 0000000000000000 x6 : 0000000000000068 [ 3.836676] x5 : ffff8000f6e1abe8 x4 : 0000000000000000 [ 3.841971] x3 : ffff00000928c868 x2 : ffff8000f6e1abec [ 3.847267] x1 : ffff00000928c868 x0 : ffff8000f6e1abe8 [ 3.852567] Process swapper/0 (pid: 1, stack limit = 0x(____ptrval____)) [ 3.857900] Call trace: [ 3.864473] __memcpy_fromio+0x68/0x80 [ 3.866683] ufs_qcom_dump_dbg_regs+0x1c0/0x370 [ 3.870522] ufshcd_print_host_regs+0x168/0x190 [ 3.874946] ufshcd_init+0xd4c/0xde0 [ 3.879459] ufshcd_pltfrm_init+0x3c8/0x550 [ 3.883264] ufs_qcom_probe+0x24/0x60 [ 3.887188] platform_drv_probe+0x50/0xa0 Assuming aligned 32-bit registers, let's use readl, after making sure that 'offset' and 'len' are indeed multiples of 4. Fixes: ba80917d ("scsi: ufs: ufshcd_dump_regs to use memcpy_fromio") Cc: <stable@vger.kernel.org> Signed-off-by:
Marc Gonzalez <marc.w.gonzalez@free.fr> Acked-by:
Tomas Winkler <tomas.winkler@intel.com> Reviewed-by:
Jeffrey Hugo <jhugo@codeaurora.org> Reviewed-by:
Bjorn Andersson <bjorn.andersson@linaro.org> Tested-by:
Evan Green <evgreen@chromium.org> Signed-off-by:
Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by:
-
Dan Williams authored
commit 11189c10 upstream. The _DSM function number validation only happens to succeed when the generic Linux command number translation corresponds with a DSM-family-specific function number. This breaks NVDIMM-N implementations that correctly implement _LSR, _LSW, and _LSI, but do not happen to publish support for DSM function numbers 4, 5, and 6. Recall that the support for _LS{I,R,W} family of methods results in the DIMM being marked as supporting those command numbers at acpi_nfit_register_dimms() time. The DSM function mask is only used for ND_CMD_CALL support of non-NVDIMM_FAMILY_INTEL devices. Fixes: 31eca76b ("nfit, libnvdimm: limited/whitelisted dimm command...") Cc: <stable@vger.kernel.org> Link: https://github.com/pmem/ndctl/issues/78Reported-by:
Sujith Pandel <sujith_pandel@dell.com> Tested-by:
Vishal Verma <vishal.l.verma@intel.com> Reviewed-by:
Jeff Moyer <jmoyer@redhat.com> Signed-off-by:
Dan Williams <dan.j.williams@intel.com> Signed-off-by:
-
Dan Williams authored
commit 5e9e38d0 upstream. In preparation for using function number 0 as an error value, prevent it from being considered a valid function value by acpi_nfit_ctl(). Cc: <stable@vger.kernel.org> Cc: stuart hayes <stuart.w.hayes@gmail.com> Fixes: e02fb726 ("nfit: add Microsoft NVDIMM DSM command set...") Reported-by:
-
Dmitry Torokhov authored
commit d77651a2 upstream. An integer overflow may arise in uinput_validate_absinfo() if "max - min" can't be represented by an "int". We should check for overflow before trying to use the result. Reported-by:
Peter Hutterer <peter.hutterer@who-t.net> Cc: stable@vger.kernel.org Signed-off-by:
Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by:
-
Deepa Dinamani authored
commit 2e746942 upstream. The usec part of the timeval is defined as __kernel_suseconds_t tv_usec; /* microseconds */ Arnd noticed that sparc64 is the only architecture that defines __kernel_suseconds_t as int rather than long. This breaks the current y2038 fix for kernel as we only access and define the timeval struct for non-kernel use cases. But, this was hidden by an another typo in the use of __KERNEL__ qualifier. Fix the typo, and provide an override for sparc64. Fixes: 152194fe ("Input: extend usable life of event timestamps to 2106 on 32 bit systems") Reported-by:
Arnd Bergmann <arnd@arndb.de> Signed-off-by:
Deepa Dinamani <deepa.kernel@gmail.com> Cc: stable@vger.kernel.org Signed-off-by:
-
Tom Panfil authored
commit fe2bfd0d upstream. Add support for the SteelSeries Stratus Duo, a wireless Xbox 360 controller. The Stratus Duo ships with a USB dongle to enable wireless connectivity, but it can also function as a wired controller by connecting it directly to a PC via USB, hence the need for two USD PIDs. 0x1430 is the dongle, and 0x1431 is the controller. Signed-off-by:
Tom Panfil <tom@steelseries.com> Cc: stable@vger.kernel.org Signed-off-by:
-
Ronnie Sahlberg authored
commit 2e5700bd upstream. Otherwise we gradually leak credits leading to potential hung session. Signed-off-by:
Ronnie Sahlberg <lsahlber@redhat.com> CC: Stable <stable@vger.kernel.org> Reviewed-by:
Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by:
Steve French <stfrench@microsoft.com> Signed-off-by:
-
