Messages in this thread | ![/](/images/icornerl.gif) | | Date | Mon, 06 Nov 2023 05:47:08 -0800 | Subject | Re: [syzbot] [bpf?] [net?] BUG: unable to handle kernel NULL pointer dereference in sk_msg_recvmsg | From | syzbot <> |
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Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue: BUG: unable to handle kernel NULL pointer dereference in sk_msg_recvmsg
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Mem abort info: ESR = 0x0000000097c38006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: Access size = 8 byte(s) SSE = 0, SRT = 3 SF = 1, AR = 0 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=0000000045ff3000 [0000000000000000] pgd=080000004d468003, p4d=080000004d468003, pud=0800000045fd2003, pmd=0000000000000000 Internal error: Oops: 0000000097c38006 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 3469 Comm: syz-executor.0 Not tainted 6.6.0-syzkaller-gd2f51b3516da #0 Hardware name: linux,dummy-virt (DT) pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) pc : page_kasan_tag include/linux/mm.h:1810 [inline] pc : lowmem_page_address include/linux/mm.h:2181 [inline] pc : kmap_local_page include/linux/highmem-internal.h:185 [inline] pc : copy_page_to_iter+0xb0/0x150 lib/iov_iter.c:379 lr : sk_msg_recvmsg+0xf8/0x37c net/core/skmsg.c:437 sp : ffff800082c1b940 x29: ffff800082c1b940 x28: 0000000000000000 x27: f9ff000006afdc00 x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 x23: 0000000000000000 x22: 0000040000000000 x21: ffff000000000000 x20: 0000000000001000 x19: ffff800082c1bd50 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000fffffdc6d2a8 x14: 0000000000000194 x13: 0000000000000000 x12: ffff80008244fe70 x11: 0000000000000001 x10: 7210c3fc147100c6 x9 : d0bd2b0aa9cf051c x8 : faff00000b25de48 x7 : 0000000000000000 x6 : fdff000006afd540 x5 : 0000000000000001 x4 : 0000000000000000 x3 : ffff800082c1bd50 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: arch_static_branch_jump arch/arm64/include/asm/jump_label.h:38 [inline] kasan_enabled include/linux/kasan-enabled.h:13 [inline] page_kasan_tag include/linux/mm.h:1809 [inline] lowmem_page_address include/linux/mm.h:2181 [inline] kmap_local_page include/linux/highmem-internal.h:185 [inline] copy_page_to_iter+0xb0/0x150 lib/iov_iter.c:379 sk_msg_recvmsg+0xf8/0x37c net/core/skmsg.c:437 unix_bpf_recvmsg net/unix/unix_bpf.c:73 [inline] unix_bpf_recvmsg+0x13c/0x4f0 net/unix/unix_bpf.c:50 unix_dgram_recvmsg+0x30/0x4c net/unix/af_unix.c:2485 sock_recvmsg_nosec net/socket.c:1044 [inline] sock_recvmsg net/socket.c:1066 [inline] sock_recvmsg net/socket.c:1062 [inline] ____sys_recvmsg+0x1d0/0x268 net/socket.c:2807 ___sys_recvmsg+0x90/0xe8 net/socket.c:2849 do_recvmmsg+0xc8/0x2f8 net/socket.c:2943 __sys_recvmmsg net/socket.c:3022 [inline] __do_sys_recvmmsg net/socket.c:3045 [inline] __se_sys_recvmmsg net/socket.c:3038 [inline] __arm64_sys_recvmmsg+0xd0/0xec net/socket.c:3038 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x48/0x114 arch/arm64/kernel/syscall.c:51 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:136 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:155 el0_svc+0x34/0xd8 arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:595 Code: 8b160320 d346fc00 8b0032a0 d503201f (f9400323) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 8b160320 add x0, x25, x22 4: d346fc00 lsr x0, x0, #6 8: 8b0032a0 add x0, x21, x0, lsl #12 c: d503201f nop * 10: f9400323 ldr x3, [x25] <-- trapping instruction
Tested on:
commit: d2f51b35 Merge tag 'rtc-6.7' of git://git.kernel.org/p.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master console output: https://syzkaller.appspot.com/x/log.txt?x=10d706eb680000 kernel config: https://syzkaller.appspot.com/x/.config?x=fe6eaf758d1d4518 dashboard link: https://syzkaller.appspot.com/bug?extid=84f695756ed0c4bb3aba compiler: aarch64-linux-gnu-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: arm64
Note: no patches were applied.
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