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BUG: unable to handle kernel paging request in pskb_expand_head

Status: closed as invalid on 2025/01/15 12:19
Subsystems: net
[Documentation on labels]
First crash: 35d, last: 17d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: slab-out-of-bounds Write in pskb_expand_head origin:lts-only C error 1 614d 681d 0/3 auto-obsoleted due to no activity on 2024/10/04 22:43
upstream Internal error in pskb_expand_head net 7 590d 615d 0/28 closed as invalid on 2023/08/28 10:04

Sample crash report:
Unable to handle kernel paging request at virtual address dfff800000000001
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
Mem abort info:
  ESR = 0x0000000096000005
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x05: level 1 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[dfff800000000001] address between user and kernel address ranges
Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 UID: 0 PID: 7545 Comm: syz.0.194 Not tainted 6.13.0-rc2-syzkaller-g2e7aff49b5da #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : _compound_head include/linux/page-flags.h:242 [inline]
pc : get_page include/linux/mm.h:1460 [inline]
pc : __skb_frag_ref include/linux/skbuff_ref.h:20 [inline]
pc : skb_frag_ref include/linux/skbuff_ref.h:32 [inline]
pc : pskb_expand_head+0x518/0x1094 net/core/skbuff.c:2300
lr : netmem_is_net_iov include/net/netmem.h:72 [inline]
lr : skb_frag_is_net_iov include/linux/skbuff.h:3583 [inline]
lr : skb_frag_page include/linux/skbuff.h:3610 [inline]
lr : __skb_frag_ref include/linux/skbuff_ref.h:20 [inline]
lr : skb_frag_ref include/linux/skbuff_ref.h:32 [inline]
lr : pskb_expand_head+0x510/0x1094 net/core/skbuff.c:2300
sp : ffff800080017860
x29: ffff800080017940 x28: 0000000000000008 x27: 0000000000000000
x26: 0000000000000001 x25: 0000000000000000 x24: 0000000000000030
x23: ffff0000ce114440 x22: ffff0000d5f72ad0 x21: 0000000000000000
x20: dfff800000000000 x19: ffff0000d5f72a00 x18: ffff800080017160
x17: ffff80008a043978 x16: ffff800080699868 x15: 0000000000000001
x14: 1fffe00019c2288c x13: 0000000000000000 x12: 0000000000000000
x11: ffff600019c2288d x10: 0000000000ff0100 x9 : 0000000000000000
x8 : 0000000000000001 x7 : 0000000000000000 x6 : 0001000001010000
x5 : ffff0000edc59c80 x4 : ffff0000ce114480 x3 : ffff800089785444
x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 _compound_head include/linux/page-flags.h:242 [inline] (P)
 get_page include/linux/mm.h:1460 [inline] (P)
 __skb_frag_ref include/linux/skbuff_ref.h:20 [inline] (P)
 skb_frag_ref include/linux/skbuff_ref.h:32 [inline] (P)
 pskb_expand_head+0x518/0x1094 net/core/skbuff.c:2300 (P)
 netmem_is_net_iov include/net/netmem.h:72 [inline] (L)
 skb_frag_is_net_iov include/linux/skbuff.h:3583 [inline] (L)
 skb_frag_page include/linux/skbuff.h:3610 [inline] (L)
 __skb_frag_ref include/linux/skbuff_ref.h:20 [inline] (L)
 skb_frag_ref include/linux/skbuff_ref.h:32 [inline] (L)
 pskb_expand_head+0x510/0x1094 net/core/skbuff.c:2300 (L)
 __skb_unclone_keeptruesize+0x80/0x24c net/core/skbuff.c:2375
 skb_unclone_keeptruesize include/linux/skbuff.h:1998 [inline]
 __tcp_retransmit_skb+0x43c/0x1404 net/ipv4/tcp_output.c:3374
 tcp_send_loss_probe+0x304/0x740 net/ipv4/tcp_output.c:2980
 tcp_write_timer_handler+0x2cc/0x7b8 net/ipv4/tcp_timer.c:710
 tcp_write_timer+0x1a0/0x314 net/ipv4/tcp_timer.c:735
 call_timer_fn+0x1b4/0x8b8 kernel/time/timer.c:1793
 expire_timers kernel/time/timer.c:1844 [inline]
 __run_timers kernel/time/timer.c:2418 [inline]
 __run_timer_base+0x56c/0x7b4 kernel/time/timer.c:2430
 run_timer_base kernel/time/timer.c:2439 [inline]
 run_timer_softirq+0xcc/0x194 kernel/time/timer.c:2449
 handle_softirqs+0x320/0xd34 kernel/softirq.c:554
 __do_softirq+0x14/0x20 kernel/softirq.c:588
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:81
 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:891
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:86
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0x1d8/0x544 kernel/softirq.c:655
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:671
 __el1_irq arch/arm64/kernel/entry-common.c:561 [inline]
 el1_interrupt+0x38/0x68 arch/arm64/kernel/entry-common.c:575
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:580
 el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:596
 __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline] (P)
 arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline] (P)
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline] (P)
 _raw_spin_unlock_irq+0x34/0x80 kernel/locking/spinlock.c:202 (P)
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline] (L)
 _raw_spin_unlock_irq+0x30/0x80 kernel/locking/spinlock.c:202 (L)
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 shmem_add_to_page_cache+0x5d8/0xa7c mm/shmem.c:830
 shmem_alloc_and_add_folio+0xa74/0x1564 mm/shmem.c:1859
 shmem_get_folio_gfp+0x554/0x1790 mm/shmem.c:2355
 shmem_get_folio mm/shmem.c:2461 [inline]
 shmem_write_begin+0x140/0x488 mm/shmem.c:3117
 generic_perform_write+0x29c/0x868 mm/filemap.c:4055
 shmem_file_write_iter+0x110/0x138 mm/shmem.c:3293
 new_sync_write fs/read_write.c:586 [inline]
 vfs_write+0x920/0xcf4 fs/read_write.c:679
 ksys_write+0x15c/0x26c fs/read_write.c:731
 __do_sys_write fs/read_write.c:742 [inline]
 __se_sys_write fs/read_write.c:739 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:739
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Code: 9a9f011b 979e77d8 9100237c d343ff88 (38746908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	9a9f011b 	csel	x27, x8, xzr, eq	// eq = none
   4:	979e77d8 	bl	0xfffffffffe79df64
   8:	9100237c 	add	x28, x27, #0x8
   c:	d343ff88 	lsr	x8, x28, #3
* 10:	38746908 	ldrb	w8, [x8, x20] <-- trapping instruction

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/16 01:06 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 2e7aff49b5da 7cbfbb3a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: unable to handle kernel paging request in pskb_expand_head
2025/01/02 23:33 upstream 0bc21e701a6f d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in pskb_expand_head
2025/01/03 12:50 upstream 0bc21e701a6f 96d578a3 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in pskb_expand_head
2024/12/29 01:01 upstream 059dd502b263 d3ccff63 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in pskb_expand_head
2024/12/28 11:16 upstream fd0584d220fe d3ccff63 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in pskb_expand_head
2024/12/27 10:19 upstream d6ef8b40d075 d3ccff63 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in pskb_expand_head
2024/12/24 00:45 upstream f07044dd0df0 444551c4 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in pskb_expand_head
2024/12/24 00:43 upstream f07044dd0df0 444551c4 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in pskb_expand_head
2024/12/19 05:32 upstream c061cf420ded 1432fc84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in pskb_expand_head
2024/12/19 01:09 upstream c061cf420ded 1432fc84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in pskb_expand_head
* Struck through repros no longer work on HEAD.