Eric Dumazet bc1fb3c53a bpf: Make sure mac_header was set before using it ... commit 0326195f52 upstream. Classic BPF has a way to load bytes starting from the mac header. Some skbs do not have a mac header, and skb_mac_header() in this case is returning a pointer that 65535 bytes after skb->head. Existing range check in bpf_internal_load_pointer_neg_helper() was properly kicking and no illegal access was happening. New sanity check in skb_mac_header() is firing, so we need to avoid it. WARNING: CPU: 1 PID: 28990 at include/linux/skbuff.h:2785 skb_mac_header include/linux/skbuff.h:2785 [inline] WARNING: CPU: 1 PID: 28990 at include/linux/skbuff.h:2785 bpf_internal_load_pointer_neg_helper+0x1b1/0x1c0 kernel/bpf/core.c:74 Modules linked in: CPU: 1 PID: 28990 Comm: syz-executor.0 Not tainted 5.19.0-rc4-syzkaller-00865-g4874fb9484be #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 RIP: 0010:skb_mac_header include/linux/skbuff.h:2785 [inline] RIP: 0010:bpf_internal_load_pointer_neg_helper+0x1b1/0x1c0 kernel/bpf/core.c:74 Code: ff ff 45 31 f6 e9 5a ff ff ff e8 aa 27 40 00 e9 3b ff ff ff e8 90 27 40 00 e9 df fe ff ff e8 86 27 40 00 eb 9e e8 2f 2c f3 ff <0f> 0b eb b1 e8 96 27 40 00 e9 79 fe ff ff 90 41 57 41 56 41 55 41 RSP: 0018:ffffc9000309f668 EFLAGS: 00010216 RAX: 0000000000000118 RBX: ffffffffffeff00c RCX: ffffc9000e417000 RDX: 0000000000040000 RSI: ffffffff81873f21 RDI: 0000000000000003 RBP: ffff8880842878c0 R08: 0000000000000003 R09: 000000000000ffff R10: 000000000000ffff R11: 0000000000000001 R12: 0000000000000004 R13: ffff88803ac56c00 R14: 000000000000ffff R15: dffffc0000000000 FS: 00007f5c88a16700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdaa9f6c058 CR3: 000000003a82c000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ____bpf_skb_load_helper_32 net/core/filter.c:276 [inline] bpf_skb_load_helper_32+0x191/0x220 net/core/filter.c:264 Fixes: f9aefd6b2a ("net: warn if mac header was not set") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220707123900.945305-1-edumazet@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-07-29 17:25:24 +02:00
..
preload	libbpf: Move BPF_SEQ_PRINTF and BPF_SNPRINTF to bpf_helpers.h	2021-05-26 10:45:41 -07:00
arraymap.c	bpf: Fix potential race in tail call compatibility check	2021-10-26 12:37:28 -07:00
bpf_inode_storage.c	bpf: Fix spelling mistakes	2021-05-24 21:13:05 -07:00
bpf_iter.c	bpf: Refactor BPF_PROG_RUN into a function	2021-08-17 00:45:07 +02:00
bpf_local_storage.c	bpf: Prevent deadlock from recursive bpf_task_storage_[get|delete]	2021-02-26 11:51:48 -08:00
bpf_lru_list.c	bpf_lru_list: Read double-checked variable once without lock	2021-02-10 15:54:26 -08:00
bpf_lru_list.h	bpf: Fix a typo "inacitve" -> "inactive"	2020-04-06 21:54:10 +02:00
bpf_lsm.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next	2021-06-17 11:54:56 -07:00
bpf_struct_ops_types.h	bpf: tcp: Support tcp_congestion_ops in bpf	2020-01-09 08:46:18 -08:00
bpf_struct_ops.c	bpf: Handle return value of BPF_PROG_TYPE_STRUCT_OPS prog	2021-09-14 11:09:50 -07:00
bpf_task_storage.c	bpf: Consolidate task_struct BTF_ID declarations	2021-08-25 10:37:05 -07:00
btf.c	bpf: Fix calling global functions from BPF_PROG_TYPE_EXT programs	2022-06-25 15:18:40 +02:00
cgroup.c	bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem.	2022-05-01 17:22:26 +02:00
core.c	bpf: Make sure mac_header was set before using it	2022-07-29 17:25:24 +02:00
cpumap.c	bpf: cpumap: Implement generic cpumap	2021-07-07 20:01:45 -07:00
devmap.c	bpf, devmap: Exclude XDP broadcast to master device	2021-08-09 23:25:14 +02:00
disasm.c	bpf: Relicense disassembler as GPL-2.0-only OR BSD-2-Clause	2021-09-02 14:49:23 +02:00
disasm.h	bpf: Relicense disassembler as GPL-2.0-only OR BSD-2-Clause	2021-09-02 14:49:23 +02:00
dispatcher.c	bpf: Remove bpf_image tree	2020-03-13 12:49:52 -07:00
hashtab.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2021-08-13 06:41:22 -07:00
helpers.c	bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem.	2022-05-01 17:22:26 +02:00
inode.c	bpf: Fix mount source show for bpffs	2022-01-27 11:05:26 +01:00
Kconfig	sock_map: Relax config dependency to CONFIG_NET	2021-07-15 18:17:49 -07:00
local_storage.c	bpf: Increase supported cgroup storage value size	2021-07-27 15:59:29 -07:00
lpm_trie.c	bpf: Allow RCU-protected lookups to happen from bh context	2021-06-24 19:41:15 +02:00
Makefile	bpf: Enable task local storage for tracing programs	2021-02-26 11:51:47 -08:00
map_in_map.c	bpf: Remember BTF of inner maps.	2021-07-15 22:31:10 +02:00
map_in_map.h	bpf: Add map_meta_equal map ops	2020-08-28 15:41:30 +02:00
map_iter.c	bpf: Introduce MEM_RDONLY flag	2022-05-01 17:22:24 +02:00
net_namespace.c	bpf: Add support for forced LINK_DETACH command	2020-08-01 20:38:28 -07:00
offload.c	bpf, offload: Replace bitwise AND by logical AND in bpf_prog_offload_info_fill	2020-02-17 16:53:49 +01:00
percpu_freelist.c	bpf: Use raw_spin_trylock() for pcpu_freelist_push/pop in NMI	2020-10-06 00:04:11 +02:00
percpu_freelist.h	bpf: Use raw_spin_trylock() for pcpu_freelist_push/pop in NMI	2020-10-06 00:04:11 +02:00
prog_iter.c	bpf: Refactor bpf_iter_reg to have separate seq_info member	2020-07-25 20:16:32 -07:00
queue_stack_maps.c	bpf: Eliminate rlimit-based memory accounting for queue_stack_maps maps	2020-12-02 18:32:46 -08:00
reuseport_array.c	bpf: Fix spelling mistakes	2021-05-24 21:13:05 -07:00
ringbuf.c	bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem.	2022-05-01 17:22:26 +02:00
stackmap.c	bpf: Fix excessive memory allocation in stack_map_alloc()	2022-06-06 08:43:42 +02:00
syscall.c	bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem.	2022-05-01 17:22:26 +02:00
sysfs_btf.c	bpf: Load and verify kernel module BTFs	2020-11-10 15:25:53 -08:00
task_iter.c	bpf: Consolidate task_struct BTF_ID declarations	2021-08-25 10:37:05 -07:00
tnum.c	bpf, tnums: Provably sound, faster, and more precise algorithm for tnum_mul	2021-06-01 13:34:15 +02:00
trampoline.c	bpf: Fix potential array overflow in bpf_trampoline_get_progs()	2022-06-06 08:43:42 +02:00
verifier.c	bpf: Stop caching subprog index in the bpf_pseudo_func insn	2022-07-12 16:34:54 +02:00