Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 UID: 0 PID: 14292 Comm: syz.1.2163 Tainted: G U W L XTNJ syzkaller #0 PREEMPT(full) Tainted: [U]=USER, [W]=WARN, [L]=SOFTLOCKUP, [X]=AUX, [T]=RANDSTRUCT, [N]=TEST, [J]=FWCTL Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:zcomp_stream_get+0x33/0xa0 drivers/block/zram/zcomp.c:113 Code: 00 00 00 00 fc ff df 41 54 55 48 89 fd 53 49 89 ec 49 c1 ec 03 4d 01 ec e8 5a b8 d5 fb e8 55 b8 d5 fb 65 48 8b 1d 15 90 ba 0d <41> 80 3c 24 00 75 4f 48 03 5d 00 31 f6 48 89 df e8 e8 92 78 05 48 RSP: 0018:ffffc90003baf488 EFLAGS: 00010283 RAX: 0000000000000516 RBX: ffff888124b0d000 RCX: ffffc9000ae99000 RDX: 0000000000080000 RSI: ffffffff85e6a00b RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000006 R09: 7277682f7665642f R10: eb9cce1e473f4118 R11: 0000000000000001 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888142f2fc00 R15: ffffea0002067280 FS: 00007f1de6ff66c0(0000) GS:ffff888124b0d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b311f7ff8 CR3: 000000004f02c000 CR4: 00000000003526f0 Call Trace: zram_write_page drivers/block/zram/zram_drv.c:1859 [inline] zram_bvec_write drivers/block/zram/zram_drv.c:1932 [inline] zram_bio_write drivers/block/zram/zram_drv.c:2373 [inline] zram_submit_bio+0xdd4/0x1df0 drivers/block/zram/zram_drv.c:2402 __submit_bio+0x304/0x690 block/blk-core.c:646 __submit_bio_noacct block/blk-core.c:692 [inline] submit_bio_noacct_nocheck+0x75c/0xc10 block/blk-core.c:757 submit_bio_noacct+0x5bd/0x1f60 block/blk-core.c:879 submit_bio_wait+0x110/0x250 block/bio.c:1388 __blkdev_direct_IO_simple+0x488/0x860 block/fops.c:99 blkdev_direct_IO+0xcc6/0x2100 block/fops.c:435 blkdev_direct_write block/fops.c:726 [inline] blkdev_write_iter+0x703/0xe00 block/fops.c:794 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x7d3/0x11d0 fs/read_write.c:686 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1de8d8f6c9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1de6ff6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f1de8fe5fa0 RCX: 00007f1de8d8f6c9 RDX: 000000100000a3d9 RSI: 0000200000000400 RDI: 0000000000000003 RBP: 00007f1de8e11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1de8fe6038 R14: 00007f1de8fe5fa0 R15: 00007ffd527f5948 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:zcomp_stream_get+0x33/0xa0 drivers/block/zram/zcomp.c:113 Code: 00 00 00 00 fc ff df 41 54 55 48 89 fd 53 49 89 ec 49 c1 ec 03 4d 01 ec e8 5a b8 d5 fb e8 55 b8 d5 fb 65 48 8b 1d 15 90 ba 0d <41> 80 3c 24 00 75 4f 48 03 5d 00 31 f6 48 89 df e8 e8 92 78 05 48 RSP: 0018:ffffc90003baf488 EFLAGS: 00010283 RAX: 0000000000000516 RBX: ffff888124b0d000 RCX: ffffc9000ae99000 RDX: 0000000000080000 RSI: ffffffff85e6a00b RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000006 R09: 7277682f7665642f R10: eb9cce1e473f4118 R11: 0000000000000001 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888142f2fc00 R15: ffffea0002067280 FS: 00007f1de6ff66c0(0000) GS:ffff888124b0d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a02d54d950 CR3: 000000004f02c000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess), 6 bytes skipped: 0: df 41 54 filds 0x54(%rcx) 3: 55 push %rbp 4: 48 89 fd mov %rdi,%rbp 7: 53 push %rbx 8: 49 89 ec mov %rbp,%r12 b: 49 c1 ec 03 shr $0x3,%r12 f: 4d 01 ec add %r13,%r12 12: e8 5a b8 d5 fb call 0xfbd5b871 17: e8 55 b8 d5 fb call 0xfbd5b871 1c: 65 48 8b 1d 15 90 ba mov %gs:0xdba9015(%rip),%rbx # 0xdba9039 23: 0d * 24: 41 80 3c 24 00 cmpb $0x0,(%r12) <-- trapping instruction 29: 75 4f jne 0x7a 2b: 48 03 5d 00 add 0x0(%rbp),%rbx 2f: 31 f6 xor %esi,%esi 31: 48 89 df mov %rbx,%rdi 34: e8 e8 92 78 05 call 0x5789321 39: 48 rex.W