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2026-04-07xsk: validate MTU against usable frame size on bindMaciej Fijalkowski1-3/+25
AF_XDP bind currently accepts zero-copy pool configurations without verifying that the device MTU fits into the usable frame space provided by the UMEM chunk. This becomes a problem since we started to respect tailroom which is subtracted from chunk_size (among with headroom). 2k chunk size might not provide enough space for standard 1500 MTU, so let us catch such settings at bind time. Furthermore, validate whether underlying HW will be able to satisfy configured MTU wrt XSK's frame size multiplied by supported Rx buffer chain length (that is exposed via net_device::xdp_zc_max_segs). Fixes: 24ea50127ecf ("xsk: support mbuf on ZC RX") Reviewed-by: Björn Töpel <bjorn@kernel.org> Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://patch.msgid.link/20260402154958.562179-5-maciej.fijalkowski@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07xsk: fix XDP_UMEM_SG_FLAG issuesMaciej Fijalkowski2-1/+5
Currently xp_assign_dev_shared() is missing XDP_USE_SG being propagated to flags so set it in order to preserve mtu check that is supposed to be done only when no multi-buffer setup is in picture. Also, this flag has the same value as XDP_UMEM_TX_SW_CSUM so we could get unexpected SG setups for software Tx checksums. Since csum flag is UAPI, modify value of XDP_UMEM_SG_FLAG. Fixes: d609f3d228a8 ("xsk: add multi-buffer support for sockets sharing umem") Reviewed-by: Björn Töpel <bjorn@kernel.org> Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://patch.msgid.link/20260402154958.562179-4-maciej.fijalkowski@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07xsk: respect tailroom for ZC setupsMaciej Fijalkowski2-3/+24
Multi-buffer XDP stores information about frags in skb_shared_info that sits at the tailroom of a packet. The storage space is reserved via xdp_data_hard_end(): ((xdp)->data_hard_start + (xdp)->frame_sz - \ SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) and then we refer to it via macro below: static inline struct skb_shared_info * xdp_get_shared_info_from_buff(const struct xdp_buff *xdp) { return (struct skb_shared_info *)xdp_data_hard_end(xdp); } Currently we do not respect this tailroom space in multi-buffer AF_XDP ZC scenario. To address this, introduce xsk_pool_get_tailroom() and use it within xsk_pool_get_rx_frame_size() which is used in ZC drivers to configure length of HW Rx buffer. Typically drivers on Rx Hw buffers side work on 128 byte alignment so let us align the value returned by xsk_pool_get_rx_frame_size() in order to avoid addressing this on driver's side. This addresses the fact that idpf uses mentioned function *before* pool->dev being set so we were at risk that after subtracting tailroom we would not provide 128-byte aligned value to HW. Since xsk_pool_get_rx_frame_size() is actively used in xsk_rcv_check() and __xsk_rcv(), add a variant of this routine that will not include 128 byte alignment and therefore old behavior is preserved. Reviewed-by: Björn Töpel <bjorn@kernel.org> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Fixes: 24ea50127ecf ("xsk: support mbuf on ZC RX") Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://patch.msgid.link/20260402154958.562179-3-maciej.fijalkowski@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07xsk: tighten UMEM headroom validation to account for tailroom and min frameMaciej Fijalkowski1-1/+2
The current headroom validation in xdp_umem_reg() could leave us with insufficient space dedicated to even receive minimum-sized ethernet frame. Furthermore if multi-buffer would come to play then skb_shared_info stored at the end of XSK frame would be corrupted. HW typically works with 128-aligned sizes so let us provide this value as bare minimum. Multi-buffer setting is known later in the configuration process so besides accounting for 128 bytes, let us also take care of tailroom space upfront. Reviewed-by: Björn Töpel <bjorn@kernel.org> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Fixes: 99e3a236dd43 ("xsk: Add missing check on user supplied headroom size") Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://patch.msgid.link/20260402154958.562179-2-maciej.fijalkowski@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07ip6_tunnel: use generic for_each_ip_tunnel_rcu macroYue Haibing1-6/+3
Remove the locally defined for_each_ip6_tunnel_rcu macro and use the generic for_each_ip_tunnel_rcu from linux/if_tunnel.h instead. This eliminates code duplication and ensures consistency across the kernel tunnel implementations. Signed-off-by: Yue Haibing <yuehaibing@huawei.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260403084619.4107978-1-yuehaibing@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07Merge branch 'properly-load-values-from-insn_arays-with-non-zero-offsets'Alexei Starovoitov3-39/+135
Anton Protopopov says: ==================== Properly load values from insn_arays with non-zero offsets The PTR_TO_INSN is always loaded via BPF_LDX_MEM instruction. However, the verifier doesn't properly verify such loads when the offset is not zero. Fix this and extend selftests with more scenarios. v2 -> v3: * Add a C-level selftest which triggers a load with nonzero offset (Alexei) * Rephrase commit messages a bit v2: https://lore.kernel.org/bpf/20260402184647.988132-1-a.s.protopopov@gmail.com/ v1: https://lore.kernel.org/bpf/20260401161529.681755-1-a.s.protopopov@gmail.com ==================== Link: https://patch.msgid.link/20260406160141.36943-1-a.s.protopopov@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07selftests/bpf: Add more tests for loading insn arrays with offsetsAnton Protopopov2-39/+115
A `gotox rX` instruction accepts only values of type PTR_TO_INSN. The only way to create such a value is to load it from a map of type insn_array: rX = *(rY + offset) # rY was read from an insn_array ... gotox rX Add instruction-level and C-level selftests to validate loads with nonzero offsets. Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com> Link: https://lore.kernel.org/r/20260406160141.36943-3-a.s.protopopov@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07bpf: Do not ignore offsets for loads from insn_arraysAnton Protopopov1-0/+20
When a pointer to PTR_TO_INSN is dereferenced, the offset field of the BPF_LDX_MEM instruction can be nonzero. Patch the verifier to not ignore this field. Reported-by: Jiyong Yang <ksur673@gmail.com> Fixes: 493d9e0d6083 ("bpf, x86: add support for indirect jumps") Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com> Link: https://lore.kernel.org/r/20260406160141.36943-2-a.s.protopopov@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07bpf: Avoid -Wflex-array-members-not-at-end warningsGustavo A. R. Silva3-12/+9
Apparently, struct bpf_empty_prog_array exists entirely to populate a single element of "items" in a global variable. "null_prog" is only used during the initializer. None of this is needed; globals will be correctly sized with an array initializer of a flexible-array member. So, remove struct bpf_empty_prog_array and adjust the rest of the code, accordingly. With these changes, fix the following warnings: ./include/linux/bpf.h:2369:31: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Acked-by: Mykyta Yatsenko <yatsenko@meta.com> Link: https://lore.kernel.org/r/acr7Whmn0br3xeBP@kspp Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07net: advance skb_defer_disable_key check in napi_consume_skbJason Xing1-1/+3
When net.core.skb_defer_max is adjusted to zero, napi_consume_skb() shouldn't go into that deeper in skb_attempt_defer_free() because it adds an additional pair of local_bh_enable/disable() which is evidently not needed. Advancing the check of the static key saves more cycles and benefits non defer case. Signed-off-by: Jason Xing <kernelxing@tencent.com> Link: https://patch.msgid.link/20260402034114.65766-1-kerneljasonxing@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07Merge branch 'net-dsa-mxl862xx-add-support-for-bridge-offloading'Jakub Kicinski7-71/+1041
Daniel Golle says: ==================== net: dsa: mxl862xx: add support for bridge offloading As a next step to complete the mxl862xx DSA driver, add support for offloading forwarding between bridged ports to the switch hardware. This works pretty much without any big surprises, apart from two subtleties: * per-port control over flooding behavior has to be implemented by (ab)using a 0-rate QoS meters as stopper in lack of any better option. * STP state transition unconditionally enables learning on a port even if it was previously explicitely disabled (a firmware bug) Note that as the driver is still lacking all VLAN features (which are going to be added next), at this point some of the bridge_vlan_aware.sh tests are failing after applying this series. This is expected and cannot be avoided without implementing port_vlan_filtering + port_vlan_add/del. And adding both bridge and VLAN offloading at the same time would be too much for anyone to review, so VLAN support is going to be submitted in a follow-up series immediately after this series has been accepted. All other relevant selftests (including bridge_vlan_unaware.sh) are still passing. Inspired by the comments received from Paolo Abeni as reply to v5 the driver now no longer caches bridge port membership in the driver, but instead imports an existing helper from yt921x.c to dsa.h in order to allow the driver to easily iterate over bridge members. The mapping between DSA bridge num and firmware bridge ID is done using a simple fixed-size array in mxl862xx_priv. ==================== Link: https://patch.msgid.link/cover.1775049897.git.daniel@makrotopia.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07net: dsa: mxl862xx: implement bridge offloadingDaniel Golle4-58/+1022
Implement joining and leaving bridges as well as add, delete and dump operations on isolated FDBs, port MDB membership management, and setting a port's STP state. The switch supports a maximum of 63 bridges, however, up to 12 may be used as "single-port bridges" to isolate standalone ports. Allowing up to 48 bridges to be offloaded seems more than enough on that hardware, hence that is set as max_num_bridges. A total of 128 bridge ports are supported in the bridge portmap, and virtual bridge ports have to be used eg. for link-aggregation, hence potentially exceeding the number of hardware ports. The firmware-assigned bridge identifier (FID) for each offloaded bridge is stored in an array used to map DSA bridge num to firmware bridge ID, avoiding the need for a driver-private bridge tracking structure. Bridge member portmaps are rebuilt on join/leave using dsa_switch_for_each_bridge_member(). As there are now more users of the BRIDGEPORT_CONFIG_SET API and the state of each port is cached locally, introduce a helper function mxl862xx_set_bridge_port(struct dsa_switch *ds, int port) which applies the cached per-port state to hardware. For standalone user ports (dp->bridge == NULL), it additionally resets the port to single-port bridge state: CPU-only portmap, learning and flooding disabled. The CPU port path sets its state explicitly before calling this helper and is therefore not affected by the reset. Note that MASK_VLAN_BASED_MAC_LEARNING is intentionally absent from the firmware write mask. After mxl862xx_reset(), the firmware initialises all VLAN-based MAC learning fields to 0 (disabled), so SVL is the active mode by default without having to set it explicitly. Note that there is no convenient way to control flooding on per-port level, so the driver is using a 0-rate QoS meter setup as a stopper in lack of any better option. In order to be perfect the firmware-enforced minimum bucket size is bypassed by directly writing 0s to the relevant registers -- without that at least one 64-byte packet could still pass before the meter would change from 'yellow' into 'red' state. Signed-off-by: Daniel Golle <daniel@makrotopia.org> Link: https://patch.msgid.link/dd079180e2098e5f9626fcd149b9bad9a1b5a1b2.1775049897.git.daniel@makrotopia.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07dsa: tag_mxl862xx: set dsa_default_offload_fwd_mark()Daniel Golle1-0/+3
The MxL862xx offloads bridge forwarding in hardware, so set dsa_default_offload_fwd_mark() to avoid duplicate forwarding of packets of (eg. flooded) frames arriving at the CPU port. Link-local frames are directly trapped to the CPU port only, so don't set dsa_default_offload_fwd_mark() on those. Signed-off-by: Daniel Golle <daniel@makrotopia.org> Link: https://patch.msgid.link/e1161c90894ddc519c57dc0224b3a0f6bfa1d2d6.1775049897.git.daniel@makrotopia.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07net: dsa: add bridge member iteration macroDaniel Golle1-3/+6
Drivers that offload bridges need to iterate over the ports that are members of a given bridge, for example to rebuild per-port forwarding bitmaps when membership changes. Currently drivers typically open-code this by combining dsa_switch_for_each_user_port() with a dsa_port_offloads_bridge_dev() check, or cache bridge membership within the driver. Add dsa_switch_for_each_bridge_member() macro to express this pattern directly, and use it for the existing dsa_bridge_ports() inline helper. Signed-off-by: Daniel Golle <daniel@makrotopia.org> Link: https://patch.msgid.link/e7136aaa26773f39e805a00fe4ecf13cd2b83fc0.1775049897.git.daniel@makrotopia.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07net: dsa: move dsa_bridge_ports() helper to dsa.hDaniel Golle2-13/+13
The yt921x driver contains a helper to create a bitmap of ports which are members of a bridge. Move the helper as static inline function into dsa.h, so other driver can make use of it as well. Signed-off-by: Daniel Golle <daniel@makrotopia.org> Link: https://patch.msgid.link/4f8bbfce3e4e3a02064fc4dc366263136c6e0383.1775049897.git.daniel@makrotopia.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07vsock: avoid timeout for non-blocking accept() with empty backlogLaurence Rowe1-9/+6
A common pattern in epoll network servers is to eagerly accept all pending connections from the non-blocking listening socket after epoll_wait indicates the socket is ready by calling accept in a loop until EAGAIN is returned indicating that the backlog is empty. Scheduling a timeout for a non-blocking accept with an empty backlog meant AF_VSOCK sockets used by epoll network servers incurred hundreds of microseconds of additional latency per accept loop compared to AF_INET or AF_UNIX sockets. Signed-off-by: Laurence Rowe <laurencerowe@gmail.com> Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://patch.msgid.link/20260402204918.130395-1-laurencerowe@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07psp: add missing device stats to get-stats reply attributesDaniel Zahka1-0/+8
Commit f05d26198cf2 ("psp: add stats from psp spec to driver facing api") added device statistics (rx-packets, rx-bytes, rx-auth-fail, rx-error, rx-bad, tx-packets, tx-bytes, tx-error) to the stats attribute-set but did not add them to the get-stats operation reply attributes. The kernel reports these attributes in the reply, so list them in the spec to match. Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260403-psp-yaml-fix-v1-1-dacee0663903@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07net: mctp: defer creation of dst after source-address checkJeremy Kerr1-11/+11
Sashiko reports: > mctp_dst_from_route() increments the device reference count by calling > mctp_dev_hold(). When a valid route is found and dst is NULL, the > structure copy is bypassed and rc is set to 0. Instead of optimistically creating a dst from the final route (then releasing it if the saddr is invalid), perform the saddr check first. This means we don't have an unuecessary hold/release on the dev, which could leak if the dst pointer is NULL. No caller passes a NULL dst at present though (so the leak is not possible), but this is an intended use of mctp_dst_from_route(). Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260403-dev-mctp-dst-defer-v1-1-9c2c55faf9e9@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07net: mctp: tests: use actual address when creating dev with addrJeremy Kerr1-1/+1
Sashiko reports: > This isn't a bug in the core networking code, but the addr parameter > appears to be ignored here. In mctp_test_create_dev_with_addr(), we are ignoring the addr argument and just using `8`. Use the passed address instead. All invocations use 8 anyway, so no effective change at present. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Simon Horman <horms@verge.net.au> Link: https://patch.msgid.link/20260403-dev-mctp-fix-test-addr-v1-1-b7fa789cdd9b@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07selftests: net: py: color the basics in the outputJakub Kicinski1-0/+20
Sometimes it's hard to spot the ok / not ok lines in the output. This is especially true for the GRO tests which retries a lot so there's a wall of non-fatal output printed. Try to color the crucial lines green / red / yellow when running in a terminal. Acked-by: Stanislav Fomichev <sdf@fomichev.me> Reviewed-by: Willem de Bruijn <willemb@google.com> Acked-by: Joe Damato <joe@dama.to> Link: https://patch.msgid.link/20260402215444.1589893-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-07Merge branch 'allow-variable-offsets-for-syscall-ptr_to_ctx'Alexei Starovoitov6-93/+703
Kumar Kartikeya Dwivedi says: ==================== Allow variable offsets for syscall PTR_TO_CTX Enable pointer modification with variable offsets accumulated in the register for PTR_TO_CTX for syscall programs where it won't be rewritten, and the context is user-supplied and checked against the max offset. See patches for details. Fixed offset support landed in [0]. By combining this set with [0], examples like the one below should succeed verification now. SEC("syscall") int prog(void *ctx) { int *arr = ctx; int i; bpf_for(i, 0, 100) arr[i] *= i; return 0; } [0]: https://lore.kernel.org/bpf/20260227005725.1247305-1-memxor@gmail.com Changelog: ---------- v4 -> v5 v4: https://lore.kernel.org/bpf/20260401122818.2240807-1-memxor@gmail.com * Use is_var_ctx_off_allowed() consistently. * Add acks. (Emil) v3 -> v4 v3: https://lore.kernel.org/bpf/20260318103526.2590079-1-memxor@gmail.com * Drop comment around describing choice of fixed or variable offsets. (Eduard) * Simplify offset adjustment for different cases. (Eduard) * Add PTR_TO_CTX case in __check_mem_access(). (Eduard) * Drop aligned access constraint from syscall_prog_is_valid_access(). * Wrap naked checks for BPF_PROG_TYPE_SYSCALL in a utility function. (Eduard) * Split tests into separate clean up and addition patches. (Eduard) * Remove CAP_SYS_ADMIN changes. (Eduard) * Enable unaligned access to syscall ctx, add tests. * Add more tests for various corner cases. * Add acks. (Puranjay, Mykyta) v2 -> v3 v2: https://lore.kernel.org/bpf/20260318075133.1031781-1-memxor@gmail.com * Prevent arg_type for KF_ARG_PTR_TO_CTX from applying to other cases due to preceding fallthrough. (Gemini/Sashiko) v1 -> v2 v1: https://lore.kernel.org/bpf/20260317111850.2107846-2-memxor@gmail.com * Harden check_func_arg_reg_off check with ARG_PTR_TO_CTX. * Add tests for unmodified ctx into tail calls. * Squash unmodified ctx change into base commit. * Add Reviewed-by's from Emil. ==================== Link: https://patch.msgid.link/20260406194403.1649608-1-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07selftests/bpf: Add tests for syscall ctx accesses beyond U16_MAXKumar Kartikeya Dwivedi1-0/+108
Ensure we reject programs that access beyond the maximum syscall ctx size, i.e. U16_MAX either through direct accesses or helpers/kfuncs. Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260406194403.1649608-8-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07selftests/bpf: Add tests for unaligned syscall ctx accessesKumar Kartikeya Dwivedi1-0/+133
Add coverage for unaligned access with fixed offsets and variable offsets, and through helpers or kfuncs. Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260406194403.1649608-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07selftests/bpf: Test modified syscall ctx for ARG_PTR_TO_CTXKumar Kartikeya Dwivedi1-0/+94
Ensure that global subprogs and tail calls can only accept an unmodified PTR_TO_CTX for syscall programs. For all other program types, fixed or variable offsets on PTR_TO_CTX is rejected when passed into an argument of any call instruction type, through the unified logic of check_func_arg_reg_off. Finally, add a positive example of a case that should succeed with all our previous changes. Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Acked-by: Puranjay Mohan <puranjay@kernel.org> Acked-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260406194403.1649608-6-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07selftests/bpf: Add syscall ctx variable offset testsKumar Kartikeya Dwivedi2-6/+267
Add various tests to exercise fixed and variable offsets on PTR_TO_CTX for syscall programs, and cover disallowed cases for other program types lacking convert_ctx_access callback. Load verifier_ctx with CAP_SYS_ADMIN so that kfunc related logic can be tested. While at it, convert assembly tests to C. Unfortunately, ctx_pointer_to_helper_2's unpriv case conflicts with usage of kfuncs in the file and cannot be run. Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Acked-by: Puranjay Mohan <puranjay@kernel.org> Acked-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260406194403.1649608-5-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07selftests/bpf: Convert ctx tests from ASM to CKumar Kartikeya Dwivedi2-45/+35
Convert existing tests from ASM to C, in prep for future changes to add more comprehensive tests. Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260406194403.1649608-4-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07bpf: Enable unaligned accesses for syscall ctxKumar Kartikeya Dwivedi1-2/+1
Don't reject usage of fixed unaligned offsets for syscall ctx. Tests will be added in later commits. Unaligned offsets already work for variable offsets. Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260406194403.1649608-3-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07bpf: Support variable offsets for syscall PTR_TO_CTXKumar Kartikeya Dwivedi3-40/+65
Allow accessing PTR_TO_CTX with variable offsets in syscall programs. Fixed offsets are already enabled for all program types that do not convert their ctx accesses, since the changes we made in the commit de6c7d99f898 ("bpf: Relax fixed offset check for PTR_TO_CTX"). Note that we also lift the restriction on passing syscall context into helpers, which was not permitted before, and passing modified syscall context into kfuncs. The structure of check_mem_access can be mostly shared and preserved, but we must use check_mem_region_access to correctly verify access with variable offsets. The check made in check_helper_mem_access is hardened to only allow PTR_TO_CTX for syscall programs to be passed in as helper memory. This was the original intention of the existing code anyway, and it makes little sense for other program types' context to be utilized as a memory buffer. In case a convincing example presents itself in the future, this check can be relaxed further. We also no longer use the last-byte access to simulate helper memory access, but instead go through check_mem_region_access. Since this no longer updates our max_ctx_offset, we must do so manually, to keep track of the maximum offset at which the program ctx may be accessed. Take care to ensure that when arg_type is ARG_PTR_TO_CTX, we do not relax any fixed or variable offset constraints around PTR_TO_CTX even in syscall programs, and require them to be passed unmodified. There are several reasons why this is necessary. First, if we pass a modified ctx, then the global subprog's accesses will not update the max_ctx_offset to its true maximum offset, and can lead to out of bounds accesses. Second, tail called program (or extension program replacing global subprog) where their max_ctx_offset exceeds the program they are being called from can also cause issues. For the latter, unmodified PTR_TO_CTX is the first requirement for the fix, the second is ensuring max_ctx_offset >= the program they are being called from, which has to be a separate change not made in this commit. All in all, we can hint using arg_type when we expect ARG_PTR_TO_CTX and make our relaxation around offsets conditional on it. Drop coverage of syscall tests from verifier_ctx.c temporarily for negative cases until they are updated in subsequent commits. Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Acked-by: Puranjay Mohan <puranjay@kernel.org> Acked-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260406194403.1649608-2-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-07e1000: check return value of e1000_read_eepromAgalakov Daniil1-1/+7
[Why] e1000_set_eeprom() performs a read-modify-write operation when the write range is not word-aligned. This requires reading the first and last words of the range from the EEPROM to preserve the unmodified bytes. However, the code does not check the return value of e1000_read_eeprom(). If the read fails, the operation continues using uninitialized data from eeprom_buff. This results in corrupted data being written back to the EEPROM for the boundary words. Add the missing error checks and abort the operation if reading fails. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Co-developed-by: Iskhakov Daniil <dish@amicon.ru> Signed-off-by: Iskhakov Daniil <dish@amicon.ru> Signed-off-by: Agalakov Daniil <ade@amicon.ru> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-04-07igb: remove napi_synchronize() in igb_down()Alex Dvoretsky1-2/+1
When an AF_XDP zero-copy application terminates abruptly (e.g., kill -9), the XSK buffer pool is destroyed but NAPI polling continues. igb_clean_rx_irq_zc() repeatedly returns the full budget, preventing napi_complete_done() from clearing NAPI_STATE_SCHED. igb_down() calls napi_synchronize() before napi_disable() for each queue vector. napi_synchronize() spins waiting for NAPI_STATE_SCHED to clear, which never happens. igb_down() blocks indefinitely, the TX watchdog fires, and the TX queue remains permanently stalled. napi_disable() already handles this correctly: it sets NAPI_STATE_DISABLE. After a full-budget poll, __napi_poll() checks napi_disable_pending(). If set, it forces completion and clears NAPI_STATE_SCHED, breaking the loop that napi_synchronize() cannot. napi_synchronize() was added in commit 41f149a285da ("igb: Fix possible panic caused by Rx traffic arrival while interface is down"). napi_disable() provides stronger guarantees: it prevents further scheduling and waits for any active poll to exit. Other Intel drivers (ixgbe, ice, i40e) use napi_disable() without a preceding napi_synchronize() in their down paths. Remove redundant napi_synchronize() call and reorder napi_disable() before igb_set_queue_napi() so the queue-to-NAPI mapping is only cleared after polling has fully stopped. Fixes: 2c6196013f84 ("igb: Add AF_XDP zero-copy Rx support") Cc: stable@vger.kernel.org Suggested-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Signed-off-by: Alex Dvoretsky <advoretsky@gmail.com> Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Tested-by: Patryk Holda <patryk.holda@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-04-06ixgbevf: add missing negotiate_features op to Hyper-V ops tableMichal Schmidt1-0/+7
Commit a7075f501bd3 ("ixgbevf: fix mailbox API compatibility by negotiating supported features") added the .negotiate_features callback to ixgbe_mac_operations and populated it in ixgbevf_mac_ops, but forgot to add it to ixgbevf_hv_mac_ops. This leaves the function pointer NULL on Hyper-V VMs. During probe, ixgbevf_negotiate_api() calls ixgbevf_set_features(), which unconditionally dereferences hw->mac.ops.negotiate_features(). On Hyper-V this results in a NULL pointer dereference: BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine [...] Workqueue: events work_for_cpu_fn RIP: 0010:0x0 [...] Call Trace: ixgbevf_negotiate_api+0x66/0x160 [ixgbevf] ixgbevf_sw_init+0xe4/0x1f0 [ixgbevf] ixgbevf_probe+0x20f/0x4a0 [ixgbevf] local_pci_probe+0x50/0xa0 work_for_cpu_fn+0x1a/0x30 [...] Add ixgbevf_hv_negotiate_features_vf() that returns -EOPNOTSUPP and wire it into ixgbevf_hv_mac_ops. The caller already handles -EOPNOTSUPP gracefully. Fixes: a7075f501bd3 ("ixgbevf: fix mailbox API compatibility by negotiating supported features") Reported-by: Xiaoqiang Xiong <xxiong@redhat.com> Closes: https://issues.redhat.com/browse/RHEL-155455 Assisted-by: Claude:claude-4.6-opus-high Cursor Tested-by: Xiaoqiang Xiong <xxiong@redhat.com> Signed-off-by: Michal Schmidt <mschmidt@redhat.com> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-04-06ixgbe: stop re-reading flash on every get_drvinfo for e610Aleksandr Loktionov4-8/+19
ixgbe_get_drvinfo() calls ixgbe_refresh_fw_version() on every ethtool query for e610 adapters. That ends up in ixgbe_discover_flash_size(), which bisects the full 16 MB NVM space issuing one ACI command per step (~20 ms each, ~24 steps total = ~500 ms). Profiling on an idle E610-XAT2 system with telegraf scraping ethtool stats every 10 seconds: kretprobe:ixgbe_get_drvinfo took 527603 us kretprobe:ixgbe_get_drvinfo took 523978 us kretprobe:ixgbe_get_drvinfo took 552975 us kretprobe:ice_get_drvinfo took 3 us kretprobe:igb_get_drvinfo took 2 us kretprobe:i40e_get_drvinfo took 5 us The half-second stall happens under the RTNL lock, causing visible latency on ip-link and friends. The FW version can only change after an EMPR reset. All flash data is already populated at probe time and the cached adapter->eeprom_id is what get_drvinfo should be returning. The only place that needs to trigger a re-read is ixgbe_devlink_reload_empr_finish(), right after the EMPR completes and new firmware is running. Additionally, refresh the FW version in ixgbe_reinit_locked() so that any PF that undergoes a reinit after an EMPR (e.g. triggered by another PF's devlink reload) also picks up the new version in adapter->eeprom_id. ixgbe_devlink_info_get() keeps its refresh call for explicit "devlink dev info" queries, which is fine given those are user-initiated. Fixes: c9e563cae19e ("ixgbe: add support for devlink reload") Co-developed-by: Jedrzej Jagielski <jedrzej.jagielski@intel.com> Signed-off-by: Jedrzej Jagielski <jedrzej.jagielski@intel.com> Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Reviewed-by: Simon Horman <horms@kernel.org> Tested-by: Rinitha S <sx.rinitha@intel.com> (A Contingent worker at Intel) Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-04-06ice: fix PTP timestamping broken by SyncE code on E825CPetr Oros1-10/+12
The E825C SyncE support added in commit ad1df4f2d591 ("ice: dpll: Support E825-C SyncE and dynamic pin discovery") introduced a SyncE reconfiguration block in ice_ptp_link_change() that prevents ice_ptp_port_phy_restart() from being called in several error paths. Without the PHY restart, PTP timestamps stop working after any link change event. There are three ways the PHY restart gets blocked: 1. When DPLL initialization fails (e.g. missing ACPI firmware node properties), ICE_FLAG_DPLL is not set and the function returns early before reaching the PHY restart. 2. When ice_tspll_bypass_mux_active_e825c() fails to read the CGU register, WARN_ON_ONCE fires and the function returns early. 3. When ice_tspll_cfg_synce_ethdiv_e825c() fails to configure the clock divider for an active pin, same early return. SyncE and PTP are independent features. SyncE reconfiguration failures must not prevent the PTP PHY restart that is essential for timestamp recovery after link changes. Fix by making the entire SyncE block conditional on ICE_FLAG_DPLL without an early return, and replacing the WARN_ON_ONCE + return error handling inside the loop with dev_err_once + break. The function always proceeds to ice_ptp_port_phy_restart() regardless of SyncE errors. Fixes: ad1df4f2d591 ("ice: dpll: Support E825-C SyncE and dynamic pin discovery") Signed-off-by: Petr Oros <poros@redhat.com> Reviewed-by: Grzegorz Nitka <grzegorz.nitka@intel.com> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Tested-by: Sunitha Mekala <sunithax.d.mekala@intel.com> (A Contingent worker at Intel) Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-04-06ice: ptp: don't WARN when controlling PF is unavailableKohei Enju1-1/+7
In VFIO passthrough setups, it is possible to pass through only a PF which doesn't own the source timer. In that case the PTP controlling PF (adapter->ctrl_pf) is never initialized in the VM, so ice_get_ctrl_ptp() returns NULL and triggers WARN_ON() in ice_ptp_setup_pf(). Since this is an expected behavior in that configuration, replace WARN_ON() with an informational message and return -EOPNOTSUPP. Fixes: e800654e85b5 ("ice: Use ice_adapter for PTP shared data instead of auxdev") Signed-off-by: Kohei Enju <kohei@enjuk.jp> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-04-06idpf: set the payload size before calling the async handlerEmil Tantilov1-0/+4
Set the payload size before forwarding the reply to the async handler. Without this, xn->reply_sz will be 0 and idpf_mac_filter_async_handler() will never get past the size check. Fixes: 34c21fa894a1 ("idpf: implement virtchnl transaction manager") Cc: stable@vger.kernel.org Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Reviewed-by: Li Li <boolli@google.com> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Samuel Salin <Samuel.salin@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-04-06idpf: improve locking around idpf_vc_xn_push_free()Emil Tantilov1-0/+2
Protect the set_bit() operation for the free_xn bitmask in idpf_vc_xn_push_free(), to make the locking consistent with rest of the code and avoid potential races in that logic. Fixes: 34c21fa894a1 ("idpf: implement virtchnl transaction manager") Cc: stable@vger.kernel.org Reported-by: Ray Zhang <sgzhang@google.com> Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Samuel Salin <Samuel.salin@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-04-06idpf: fix PREEMPT_RT raw/bh spinlock nesting for async VC handlingEmil Tantilov2-11/+8
Switch from using the completion's raw spinlock to a local lock in the idpf_vc_xn struct. The conversion is safe because complete/_all() are called outside the lock and there is no reason to share the completion lock in the current logic. This avoids invalid wait context reported by the kernel due to the async handler taking BH spinlock: [ 805.726977] ============================= [ 805.726991] [ BUG: Invalid wait context ] [ 805.727006] 7.0.0-rc2-net-devq-031026+ #28 Tainted: G S OE [ 805.727026] ----------------------------- [ 805.727038] kworker/u261:0/572 is trying to lock: [ 805.727051] ff190da6a8dbb6a0 (&vport_config->mac_filter_list_lock){+...}-{3:3}, at: idpf_mac_filter_async_handler+0xe9/0x260 [idpf] [ 805.727099] other info that might help us debug this: [ 805.727111] context-{5:5} [ 805.727119] 3 locks held by kworker/u261:0/572: [ 805.727132] #0: ff190da6db3e6148 ((wq_completion)idpf-0000:83:00.0-mbx){+.+.}-{0:0}, at: process_one_work+0x4b5/0x730 [ 805.727163] #1: ff3c6f0a6131fe50 ((work_completion)(&(&adapter->mbx_task)->work)){+.+.}-{0:0}, at: process_one_work+0x1e5/0x730 [ 805.727191] #2: ff190da765190020 (&x->wait#34){+.+.}-{2:2}, at: idpf_recv_mb_msg+0xc8/0x710 [idpf] [ 805.727218] stack backtrace: ... [ 805.727238] Workqueue: idpf-0000:83:00.0-mbx idpf_mbx_task [idpf] [ 805.727247] Call Trace: [ 805.727249] <TASK> [ 805.727251] dump_stack_lvl+0x77/0xb0 [ 805.727259] __lock_acquire+0xb3b/0x2290 [ 805.727268] ? __irq_work_queue_local+0x59/0x130 [ 805.727275] lock_acquire+0xc6/0x2f0 [ 805.727277] ? idpf_mac_filter_async_handler+0xe9/0x260 [idpf] [ 805.727284] ? _printk+0x5b/0x80 [ 805.727290] _raw_spin_lock_bh+0x38/0x50 [ 805.727298] ? idpf_mac_filter_async_handler+0xe9/0x260 [idpf] [ 805.727303] idpf_mac_filter_async_handler+0xe9/0x260 [idpf] [ 805.727310] idpf_recv_mb_msg+0x1c8/0x710 [idpf] [ 805.727317] process_one_work+0x226/0x730 [ 805.727322] worker_thread+0x19e/0x340 [ 805.727325] ? __pfx_worker_thread+0x10/0x10 [ 805.727328] kthread+0xf4/0x130 [ 805.727333] ? __pfx_kthread+0x10/0x10 [ 805.727336] ret_from_fork+0x32c/0x410 [ 805.727345] ? __pfx_kthread+0x10/0x10 [ 805.727347] ret_from_fork_asm+0x1a/0x30 [ 805.727354] </TASK> Fixes: 34c21fa894a1 ("idpf: implement virtchnl transaction manager") Cc: stable@vger.kernel.org Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reported-by: Ray Zhang <sgzhang@google.com> Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Samuel Salin <Samuel.salin@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-04-06kunit: tool: Terminate kernel under test on SIGINTDavid Gow1-9/+19
kunit.py will attempt to catch SIGINT / ^C in order to ensure the TTY isn't messed up, but never actually attempts to terminate the running kernel (be it UML or QEMU). This can lead to a bit of frustration if the kernel has crashed or hung. Terminate the kernel process in the signal handler, if it's running. This requires plumbing through the process handle in a few more places (and having some checks to see if the kernel is still running in places where it may have already been killed). Reported-by: Andy Shevchenko <andriy.shevchenko@intel.com> Closes: https://lore.kernel.org/all/aaFmiAmg9S18EANA@smile.fi.intel.com/ Signed-off-by: David Gow <david@davidgow.net> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Tested-by: Andy Shevchenko <andriy.shevchenko@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-04-06kunit: tool: skip stty when stdin is not a ttyShuvam Pandey2-2/+50
run_kernel() cleanup and signal_handler() invoke stty unconditionally. When stdin is not a tty (for example in CI or unit tests), this writes noise to stderr. Call stty only when stdin is a tty. Add regression tests for these paths: - run_kernel() with non-tty stdin - signal_handler() with non-tty stdin - signal_handler() with tty stdin Signed-off-by: Shuvam Pandey <shuvampandey1@gmail.com> Reviewed-by: David Gow <david@davidgow.net> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-04-06kunit: tool: Recommend --raw_output=all if no KTAP foundDavid Gow1-1/+2
If no KTAP header is found in the kernel output (e.g., because the kernel crashed before the KUnit executor was run), it's very useful to re-run the test with --raw_output=all, as that will show any error output (such as a stacktrace, log message, BUG, etc). This is not particularly intuitive, however, as --raw_output=all is not well known. Add an extra log line to advertise --raw_output=all in this case, as it's a terrible user experience to just get "Did any KUnit tests run?" Signed-off-by: David Gow <david@davidgow.net> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-04-06kunit: Add --list_suites to show suitesRyota Sakamoto2-5/+27
Currently, kunit.py allows listing all individual tests via --list_tests. However, users often need to see only the available test suites. Add --list_suites to show suites. This option parses the test list output from the kernel and prints only the suite names. Example of the output of --list_suites: example_init miscdev_init printk-ringbuffer Signed-off-by: Ryota Sakamoto <sakamo.ryota@gmail.com> Reviewed-by: David Gow <david@davidgow.net> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-04-06blk-wbt: remove WARN_ON_ONCE from wbt_init_enable_default()Yuto Ohnuki1-2/+3
wbt_init_enable_default() uses WARN_ON_ONCE to check for failures from wbt_alloc() and wbt_init(). However, both are expected failure paths: - wbt_alloc() can return NULL under memory pressure (-ENOMEM) - wbt_init() can fail with -EBUSY if wbt is already registered syzbot triggers this by injecting memory allocation failures during MTD partition creation via ioctl(BLKPG), causing a spurious warning. wbt_init_enable_default() is a best-effort initialization called from blk_register_queue() with a void return type. Failure simply means the disk operates without writeback throttling, which is harmless. Replace WARN_ON_ONCE with plain if-checks, consistent with how wbt_set_lat() in the same file already handles these failures. Add a pr_warn() for the wbt_init() failure to retain diagnostic information without triggering a full stack trace. Reported-by: syzbot+71fcf20f7c1e5043d78c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=71fcf20f7c1e5043d78c Fixes: 41afaeeda509 ("blk-wbt: fix possible deadlock to nest pcpu_alloc_mutex under q_usage_counter") Signed-off-by: Yuto Ohnuki <ytohnuki@amazon.com> Reviewed-by: Yu Kuai <yukuai@fnnas.com> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Link: https://patch.msgid.link/20260316070358.65225-2-ytohnuki@amazon.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-04-06ocfs2: fix out-of-bounds write in ocfs2_write_end_inlineJoseph Qi1-0/+10
KASAN reports a use-after-free write of 4086 bytes in ocfs2_write_end_inline, called from ocfs2_write_end_nolock during a copy_file_range splice fallback on a corrupted ocfs2 filesystem mounted on a loop device. The actual bug is an out-of-bounds write past the inode block buffer, not a true use-after-free. The write overflows into an adjacent freed page, which KASAN reports as UAF. The root cause is that ocfs2_try_to_write_inline_data trusts the on-disk id_count field to determine whether a write fits in inline data. On a corrupted filesystem, id_count can exceed the physical maximum inline data capacity, causing writes to overflow the inode block buffer. Call trace (crash path): vfs_copy_file_range (fs/read_write.c:1634) do_splice_direct splice_direct_to_actor iter_file_splice_write ocfs2_file_write_iter generic_perform_write ocfs2_write_end ocfs2_write_end_nolock (fs/ocfs2/aops.c:1949) ocfs2_write_end_inline (fs/ocfs2/aops.c:1915) memcpy_from_folio <-- KASAN: write OOB So add id_count upper bound check in ocfs2_validate_inode_block() to alongside the existing i_size check to fix it. Link: https://lkml.kernel.org/r/20260403063830.3662739-1-joseph.qi@linux.alibaba.com Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reported-by: syzbot+62c1793956716ea8b28a@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=62c1793956716ea8b28a Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Cc: Heming Zhao <heming.zhao@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-06mm/damon/stat: deallocate damon_call() failure leaking damon_ctxSeongJae Park1-0/+7
damon_stat_start() always allocates the module's damon_ctx object (damon_stat_context). Meanwhile, if damon_call() in the function fails, the damon_ctx object is not deallocated. Hence, if the damon_call() is failed, and the user writes Y to “enabled” again, the previously allocated damon_ctx object is leaked. This cannot simply be fixed by deallocating the damon_ctx object when damon_call() fails. That's because damon_call() failure doesn't guarantee the kdamond main function, which accesses the damon_ctx object, is completely finished. In other words, if damon_stat_start() deallocates the damon_ctx object after damon_call() failure, the not-yet-terminated kdamond could access the freed memory (use-after-free). Fix the leak while avoiding the use-after-free by keeping returning damon_stat_start() without deallocating the damon_ctx object after damon_call() failure, but deallocating it when the function is invoked again and the kdamond is completely terminated. If the kdamond is not yet terminated, simply return -EAGAIN, as the kdamond will soon be terminated. The issue was discovered [1] by sashiko. Link: https://lkml.kernel.org/r/20260402134418.74121-1-sj@kernel.org Link: https://lore.kernel.org/20260401012428.86694-1-sj@kernel.org [1] Fixes: 405f61996d9d ("mm/damon/stat: use damon_call() repeat mode instead of damon_callback") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: <stable@vger.kernel.org> # 6.17.x Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-06mm/vma: fix memory leak in __mmap_region()Sechang Lim1-0/+7
commit 605f6586ecf7 ("mm/vma: do not leak memory when .mmap_prepare swaps the file") handled the success path by skipping get_file() via file_doesnt_need_get, but missed the error path. When /dev/zero is mmap'd with MAP_SHARED, mmap_zero_prepare() calls shmem_zero_setup_desc() which allocates a new shmem file to back the mapping. If __mmap_new_vma() subsequently fails, this replacement file is never fput()'d - the original is released by ksys_mmap_pgoff(), but nobody releases the new one. Add fput() for the swapped file in the error path. Reproducible with fault injection. FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 1 CPU: 2 UID: 0 PID: 366 Comm: syz.7.14 Not tainted 7.0.0-rc6 #2 PREEMPT(full) Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x164/0x1f0 should_fail_ex+0x525/0x650 should_failslab+0xdf/0x140 kmem_cache_alloc_noprof+0x78/0x630 vm_area_alloc+0x24/0x160 __mmap_region+0xf6b/0x2660 mmap_region+0x2eb/0x3a0 do_mmap+0xc79/0x1240 vm_mmap_pgoff+0x252/0x4c0 ksys_mmap_pgoff+0xf8/0x120 __x64_sys_mmap+0x12a/0x190 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x76/0x7e </TASK> kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) BUG: memory leak unreferenced object 0xffff8881118aca80 (size 360): comm "syz.7.14", pid 366, jiffies 4294913255 hex dump (first 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... ff ff ff ff ff ff ff ff c0 28 4d ae ff ff ff ff .........(M..... backtrace (crc db0f53bc): kmem_cache_alloc_noprof+0x3ab/0x630 alloc_empty_file+0x5a/0x1e0 alloc_file_pseudo+0x135/0x220 __shmem_file_setup+0x274/0x420 shmem_zero_setup_desc+0x9c/0x170 mmap_zero_prepare+0x123/0x140 __mmap_region+0xdda/0x2660 mmap_region+0x2eb/0x3a0 do_mmap+0xc79/0x1240 vm_mmap_pgoff+0x252/0x4c0 ksys_mmap_pgoff+0xf8/0x120 __x64_sys_mmap+0x12a/0x190 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x76/0x7e Found by syzkaller. Link: https://lkml.kernel.org/r/20260331180811.1333348-1-rhkrqnwk98@gmail.com Fixes: 605f6586ecf7 ("mm/vma: do not leak memory when .mmap_prepare swaps the file") Signed-off-by: Sechang Lim <rhkrqnwk98@gmail.com> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Pedro Falcato <pfalcato@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-06mm/memory_hotplug: maintain N_NORMAL_MEMORY during hotplugHao Li1-0/+20
N_NORMAL_MEMORY is initialized from zone population at boot, but memory hotplug currently only updates N_MEMORY. As a result, a node that gains normal memory via hotplug can remain invisible to users iterating over N_NORMAL_MEMORY, while a node that loses its last normal memory can stay incorrectly marked as such. The most visible effect is that /sys/devices/system/node/has_normal_memory does not report a node even after that node has gained normal memory via hotplug. Also, list_lru-based shrinkers can undercount objects on such a node and may skip reclaim on that node entirely, which can lead to a higher memory footprint than expected. Restore N_NORMAL_MEMORY maintenance directly in online_pages() and offline_pages(). Set the bit when a node that currently lacks normal memory onlines pages into a zone <= ZONE_NORMAL, and clear it when offlining removes the last present pages from zones <= ZONE_NORMAL. This restores the intended semantics without bringing back the old status_change_nid_normal notifier plumbing which was removed in 8d2882a8edb8. Current users that benefit include list_lru, zswap, nfsd filecache, hugetlb_cgroup, and has_normal_memory sysfs reporting. Link: https://lkml.kernel.org/r/20260330035941.518186-1-hao.li@linux.dev Fixes: 8d2882a8edb8 ("mm,memory_hotplug: remove status_change_nid_normal and update documentation") Signed-off-by: Hao Li <hao.li@linux.dev> Reviewed-by: Harry Yoo (Oracle) <harry@kernel.org> Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Reviewed-by: Joshua Hahn <joshua.hahnjy@gmail.com> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-06mm/damon/sysfs: dealloc repeat_call_control if damon_call() failsSeongJae Park1-1/+2
damon_call() for repeat_call_control of DAMON_SYSFS could fail if somehow the kdamond is stopped before the damon_call(). It could happen, for example, when te damon context was made for monitroing of a virtual address processes, and the process is terminated immediately, before the damon_call() invocation. In the case, the dyanmically allocated repeat_call_control is not deallocated and leaked. Fix the leak by deallocating the repeat_call_control under the damon_call() failure. This issue is discovered by sashiko [1]. Link: https://lkml.kernel.org/r/20260327003224.55752-1-sj@kernel.org Link: https://lore.kernel.org/20260320020630.962-1-sj@kernel.org [1] Fixes: 04a06b139ec0 ("mm/damon/sysfs: use dynamically allocated repeat mode damon_call_control") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: <stable@vger.kernel.org> [6.17+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-06mm: reinstate unconditional writeback start in balance_dirty_pages()Joanne Koong1-0/+21
Commit 64dd89ae01f2 ("mm/block/fs: remove laptop_mode") removed this unconditional writeback start from balance_dirty_pages(): if (unlikely(!writeback_in_progress(wb))) wb_start_background_writeback(wb); This logic needs to be reinstated to prevent performance regressions for strictlimited BDIs and memcg setups. The problem occurs because: a) For strictlimited BDIs, throttling is calculated using per-wb thresholds. The per-wb threshold can be exceeded even when the global dirty threshold was not exceeded (nr_dirty < gdtc->bg_thresh) b) For memcg-based throttling, memcg uses its own dirty count / thresholds and can trigger throttling even when the global threshold isn't exceeded Without the unconditional writeback start, IO is throttled as it waits for dirty pages to be written back but there is no writeback running. This leads to severe stalls. On fuse, buffered write performance dropped from 1400 MiB/s to 2000 KiB/s. Reinstate the unconditional writeback start so that writeback is guaranteed to be running whenever IO needs to be throttled. Link: https://lkml.kernel.org/r/20260326215127.3857682-2-joannelkoong@gmail.com Fixes: 64dd89ae01f2 ("mm/block/fs: remove laptop_mode") Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-06liveupdate: propagate file deserialization failuresLeo Timmins1-2/+7
luo_session_deserialize() ignored the return value from luo_file_deserialize(). As a result, a session could be left partially restored even though the /dev/liveupdate open path treats deserialization failures as fatal. Propagate the error so a failed file deserialization aborts session deserialization instead of silently continuing. Link: https://lkml.kernel.org/r/20260325044608.8407-1-leotimmins1974@gmail.com Link: https://lkml.kernel.org/r/20260325044608.8407-2-leotimmins1974@gmail.com Fixes: 16cec0d26521 ("liveupdate: luo_session: add ioctls for file preservation") Signed-off-by: Leo Timmins <leotimmins1974@gmail.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Pratyush Yadav <pratyush@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-06mm: filemap: fix nr_pages calculation overflow in filemap_map_pages()Baolin Wang1-3/+8
When running stress-ng on my Arm64 machine with v7.0-rc3 kernel, I encountered some very strange crash issues showing up as "Bad page state": " [ 734.496287] BUG: Bad page state in process stress-ng-env pfn:415735fb [ 734.496427] page: refcount:0 mapcount:1 mapping:0000000000000000 index:0x4cf316 pfn:0x415735fb [ 734.496434] flags: 0x57fffe000000800(owner_2|node=1|zone=2|lastcpupid=0x3ffff) [ 734.496439] raw: 057fffe000000800 0000000000000000 dead000000000122 0000000000000000 [ 734.496440] raw: 00000000004cf316 0000000000000000 0000000000000000 0000000000000000 [ 734.496442] page dumped because: nonzero mapcount " After analyzing this page’s state, it is hard to understand why the mapcount is not 0 while the refcount is 0, since this page is not where the issue first occurred. By enabling the CONFIG_DEBUG_VM config, I can reproduce the crash as well and captured the first warning where the issue appears: " [ 734.469226] page: refcount:33 mapcount:0 mapping:00000000bef2d187 index:0x81a0 pfn:0x415735c0 [ 734.469304] head: order:5 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 734.469315] memcg:ffff000807a8ec00 [ 734.469320] aops:ext4_da_aops ino:100b6f dentry name(?):"stress-ng-mmaptorture-9397-0-2736200540" [ 734.469335] flags: 0x57fffe400000069(locked|uptodate|lru|head|node=1|zone=2|lastcpupid=0x3ffff) ...... [ 734.469364] page dumped because: VM_WARN_ON_FOLIO((_Generic((page + nr_pages - 1), const struct page *: (const struct folio *)_compound_head(page + nr_pages - 1), struct page *: (struct folio *)_compound_head(page + nr_pages - 1))) != folio) [ 734.469390] ------------[ cut here ]------------ [ 734.469393] WARNING: ./include/linux/rmap.h:351 at folio_add_file_rmap_ptes+0x3b8/0x468, CPU#90: stress-ng-mlock/9430 [ 734.469551] folio_add_file_rmap_ptes+0x3b8/0x468 (P) [ 734.469555] set_pte_range+0xd8/0x2f8 [ 734.469566] filemap_map_folio_range+0x190/0x400 [ 734.469579] filemap_map_pages+0x348/0x638 [ 734.469583] do_fault_around+0x140/0x198 ...... [ 734.469640] el0t_64_sync+0x184/0x188 " The code that triggers the warning is: "VM_WARN_ON_FOLIO(page_folio(page + nr_pages - 1) != folio, folio)", which indicates that set_pte_range() tried to map beyond the large folio’s size. By adding more debug information, I found that 'nr_pages' had overflowed in filemap_map_pages(), causing set_pte_range() to establish mappings for a range exceeding the folio size, potentially corrupting fields of pages that do not belong to this folio (e.g., page->_mapcount). After above analysis, I think the possible race is as follows: CPU 0 CPU 1 filemap_map_pages() ext4_setattr() //get and lock folio with old inode->i_size next_uptodate_folio() ....... //shrink the inode->i_size i_size_write(inode, attr->ia_size); //calculate the end_pgoff with the new inode->i_size file_end = DIV_ROUND_UP(i_size_read(mapping->host), PAGE_SIZE) - 1; end_pgoff = min(end_pgoff, file_end); ...... //nr_pages can be overflowed, cause xas.xa_index > end_pgoff end = folio_next_index(folio) - 1; nr_pages = min(end, end_pgoff) - xas.xa_index + 1; ...... //map large folio filemap_map_folio_range() ...... //truncate folios truncate_pagecache(inode, inode->i_size); To fix this issue, move the 'end_pgoff' calculation before next_uptodate_folio(), so the retrieved folio stays consistent with the file end to avoid 'nr_pages' calculation overflow. After this patch, the crash issue is gone. Link: https://lkml.kernel.org/r/1cf1ac59018fc647a87b0dad605d4056a71c14e4.1773739704.git.baolin.wang@linux.alibaba.com Fixes: 743a2753a02e ("filemap: cap PTE range to be created to allowed zero fill in folio_map_range()") Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reported-by: Yuanhe Shu <xiangzao@linux.alibaba.com> Tested-by: Yuanhe Shu <xiangzao@linux.alibaba.com> Acked-by: Kiryl Shutsemau (Meta) <kas@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Daniel Gomez <da.gomez@samsung.com> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Dave Chinner <dchinner@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Luis Chamberalin <mcgrof@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Pankaj Raghav <p.raghav@samsung.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>