https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-6.1.y 2024-12-14T18:54:35Z 2024-12-14T18:54:35Z Maciej Fijalkowski maciej.fijalkowski@intel.com 2024-11-22T12:10:30Z urn:sha1:98c03d05936d846073df8f550e9e8bf0dde1d77f commit ab244dd7cf4c291f82faacdc50b45cc0f55b674d upstream. Jordy reported issue against XSKMAP which also applies to DEVMAP - the index used for accessing map entry, due to being a signed integer, causes the OOB writes. Fix is simple as changing the type from int to u32, however, when compared to XSKMAP case, one more thing needs to be addressed. When map is released from system via dev_map_free(), we iterate through all of the entries and an iterator variable is also an int, which implies OOB accesses. Again, change it to be u32. Example splat below: [ 160.724676] BUG: unable to handle page fault for address: ffffc8fc2c001000 [ 160.731662] #PF: supervisor read access in kernel mode [ 160.736876] #PF: error_code(0x0000) - not-present page [ 160.742095] PGD 0 P4D 0 [ 160.744678] Oops: Oops: 0000 [#1] PREEMPT SMP [ 160.749106] CPU: 1 UID: 0 PID: 520 Comm: kworker/u145:12 Not tainted 6.12.0-rc1+ #487 [ 160.757050] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019 [ 160.767642] Workqueue: events_unbound bpf_map_free_deferred [ 160.773308] RIP: 0010:dev_map_free+0x77/0x170 [ 160.777735] Code: 00 e8 fd 91 ed ff e8 b8 73 ed ff 41 83 7d 18 19 74 6e 41 8b 45 24 49 8b bd f8 00 00 00 31 db 85 c0 74 48 48 63 c3 48 8d 04 c7 <48> 8b 28 48 85 ed 74 30 48 8b 7d 18 48 85 ff 74 05 e8 b3 52 fa ff [ 160.796777] RSP: 0018:ffffc9000ee1fe38 EFLAGS: 00010202 [ 160.802086] RAX: ffffc8fc2c001000 RBX: 0000000080000000 RCX: 0000000000000024 [ 160.809331] RDX: 0000000000000000 RSI: 0000000000000024 RDI: ffffc9002c001000 [ 160.816576] RBP: 0000000000000000 R08: 0000000000000023 R09: 0000000000000001 [ 160.823823] R10: 0000000000000001 R11: 00000000000ee6b2 R12: dead000000000122 [ 160.831066] R13: ffff88810c928e00 R14: ffff8881002df405 R15: 0000000000000000 [ 160.838310] FS: 0000000000000000(0000) GS:ffff8897e0c40000(0000) knlGS:0000000000000000 [ 160.846528] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 160.852357] CR2: ffffc8fc2c001000 CR3: 0000000005c32006 CR4: 00000000007726f0 [ 160.859604] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 160.866847] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 160.874092] PKRU: 55555554 [ 160.876847] Call Trace: [ 160.879338] <TASK> [ 160.881477] ? __die+0x20/0x60 [ 160.884586] ? page_fault_oops+0x15a/0x450 [ 160.888746] ? search_extable+0x22/0x30 [ 160.892647] ? search_bpf_extables+0x5f/0x80 [ 160.896988] ? exc_page_fault+0xa9/0x140 [ 160.900973] ? asm_exc_page_fault+0x22/0x30 [ 160.905232] ? dev_map_free+0x77/0x170 [ 160.909043] ? dev_map_free+0x58/0x170 [ 160.912857] bpf_map_free_deferred+0x51/0x90 [ 160.917196] process_one_work+0x142/0x370 [ 160.921272] worker_thread+0x29e/0x3b0 [ 160.925082] ? rescuer_thread+0x4b0/0x4b0 [ 160.929157] kthread+0xd4/0x110 [ 160.932355] ? kthread_park+0x80/0x80 [ 160.936079] ret_from_fork+0x2d/0x50 [ 160.943396] ? kthread_park+0x80/0x80 [ 160.950803] ret_from_fork_asm+0x11/0x20 [ 160.958482] </TASK> Fixes: 546ac1ffb70d ("bpf: add devmap, a map for storing net device references") CC: stable@vger.kernel.org Reported-by: Jordy Zomer <jordyzomer@google.com> Suggested-by: Jordy Zomer <jordyzomer@google.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://lore.kernel.org/r/20241122121030.716788-3-maciej.fijalkowski@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 2024-11-01T00:55:56Z Florian Kauer florian.kauer@linutronix.de 2024-09-11T08:41:18Z urn:sha1:a778fbe087c19f4ece5f5fc14173328f070c3803 [ Upstream commit ca9984c5f0ab3690d98b13937b2485a978c8dd73 ] rxq contains a pointer to the device from where the redirect happened. Currently, the BPF program that was executed after a redirect via BPF_MAP_TYPE_DEVMAP* does not have it set. This is particularly bad since accessing ingress_ifindex, e.g. SEC("xdp") int prog(struct xdp_md *pkt) { return bpf_redirect_map(&dev_redirect_map, 0, 0); } SEC("xdp/devmap") int prog_after_redirect(struct xdp_md *pkt) { bpf_printk("ifindex %i", pkt->ingress_ifindex); return XDP_PASS; } depends on access to rxq, so a NULL pointer gets dereferenced: <1>[ 574.475170] BUG: kernel NULL pointer dereference, address: 0000000000000000 <1>[ 574.475188] #PF: supervisor read access in kernel mode <1>[ 574.475194] #PF: error_code(0x0000) - not-present page <6>[ 574.475199] PGD 0 P4D 0 <4>[ 574.475207] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI <4>[ 574.475217] CPU: 4 UID: 0 PID: 217 Comm: kworker/4:1 Not tainted 6.11.0-rc5-reduced-00859-g780801200300 #23 <4>[ 574.475226] Hardware name: Intel(R) Client Systems NUC13ANHi7/NUC13ANBi7, BIOS ANRPL357.0026.2023.0314.1458 03/14/2023 <4>[ 574.475231] Workqueue: mld mld_ifc_work <4>[ 574.475247] RIP: 0010:bpf_prog_5e13354d9cf5018a_prog_after_redirect+0x17/0x3c <4>[ 574.475257] Code: cc cc cc cc cc cc cc 80 00 00 00 cc cc cc cc cc cc cc cc f3 0f 1e fa 0f 1f 44 00 00 66 90 55 48 89 e5 f3 0f 1e fa 48 8b 57 20 <48> 8b 52 00 8b 92 e0 00 00 00 48 bf f8 a6 d5 c4 5d a0 ff ff be 0b <4>[ 574.475263] RSP: 0018:ffffa62440280c98 EFLAGS: 00010206 <4>[ 574.475269] RAX: ffffa62440280cd8 RBX: 0000000000000001 RCX: 0000000000000000 <4>[ 574.475274] RDX: 0000000000000000 RSI: ffffa62440549048 RDI: ffffa62440280ce0 <4>[ 574.475278] RBP: ffffa62440280c98 R08: 0000000000000002 R09: 0000000000000001 <4>[ 574.475281] R10: ffffa05dc8b98000 R11: ffffa05f577fca40 R12: ffffa05dcab24000 <4>[ 574.475285] R13: ffffa62440280ce0 R14: ffffa62440549048 R15: ffffa62440549000 <4>[ 574.475289] FS: 0000000000000000(0000) GS:ffffa05f4f700000(0000) knlGS:0000000000000000 <4>[ 574.475294] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4>[ 574.475298] CR2: 0000000000000000 CR3: 000000025522e000 CR4: 0000000000f50ef0 <4>[ 574.475303] PKRU: 55555554 <4>[ 574.475306] Call Trace: <4>[ 574.475313] <IRQ> <4>[ 574.475318] ? __die+0x23/0x70 <4>[ 574.475329] ? page_fault_oops+0x180/0x4c0 <4>[ 574.475339] ? skb_pp_cow_data+0x34c/0x490 <4>[ 574.475346] ? kmem_cache_free+0x257/0x280 <4>[ 574.475357] ? exc_page_fault+0x67/0x150 <4>[ 574.475368] ? asm_exc_page_fault+0x26/0x30 <4>[ 574.475381] ? bpf_prog_5e13354d9cf5018a_prog_after_redirect+0x17/0x3c <4>[ 574.475386] bq_xmit_all+0x158/0x420 <4>[ 574.475397] __dev_flush+0x30/0x90 <4>[ 574.475407] veth_poll+0x216/0x250 [veth] <4>[ 574.475421] __napi_poll+0x28/0x1c0 <4>[ 574.475430] net_rx_action+0x32d/0x3a0 <4>[ 574.475441] handle_softirqs+0xcb/0x2c0 <4>[ 574.475451] do_softirq+0x40/0x60 <4>[ 574.475458] </IRQ> <4>[ 574.475461] <TASK> <4>[ 574.475464] __local_bh_enable_ip+0x66/0x70 <4>[ 574.475471] __dev_queue_xmit+0x268/0xe40 <4>[ 574.475480] ? selinux_ip_postroute+0x213/0x420 <4>[ 574.475491] ? alloc_skb_with_frags+0x4a/0x1d0 <4>[ 574.475502] ip6_finish_output2+0x2be/0x640 <4>[ 574.475512] ? nf_hook_slow+0x42/0xf0 <4>[ 574.475521] ip6_finish_output+0x194/0x300 <4>[ 574.475529] ? __pfx_ip6_finish_output+0x10/0x10 <4>[ 574.475538] mld_sendpack+0x17c/0x240 <4>[ 574.475548] mld_ifc_work+0x192/0x410 <4>[ 574.475557] process_one_work+0x15d/0x380 <4>[ 574.475566] worker_thread+0x29d/0x3a0 <4>[ 574.475573] ? __pfx_worker_thread+0x10/0x10 <4>[ 574.475580] ? __pfx_worker_thread+0x10/0x10 <4>[ 574.475587] kthread+0xcd/0x100 <4>[ 574.475597] ? __pfx_kthread+0x10/0x10 <4>[ 574.475606] ret_from_fork+0x31/0x50 <4>[ 574.475615] ? __pfx_kthread+0x10/0x10 <4>[ 574.475623] ret_from_fork_asm+0x1a/0x30 <4>[ 574.475635] </TASK> <4>[ 574.475637] Modules linked in: veth br_netfilter bridge stp llc iwlmvm x86_pkg_temp_thermal iwlwifi efivarfs nvme nvme_core <4>[ 574.475662] CR2: 0000000000000000 <4>[ 574.475668] ---[ end trace 0000000000000000 ]--- Therefore, provide it to the program by setting rxq properly. Fixes: cb261b594b41 ("bpf: Run devmap xdp_prog on flush instead of bulk enqueue") Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Florian Kauer <florian.kauer@linutronix.de> Acked-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20240911-devel-koalo-fix-ingress-ifindex-v4-1-5c643ae10258@linutronix.de Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>