On 1/3/21 1:40 PM, Toralf Förster wrote: > On 12/30/20 10:05 AM, Toralf Förster wrote: >> On 12/29/20 11:55 PM, Randy Dunlap wrote: >>>> No, this is wrong. 'size' in this case is the size of the read. >>>> And it's zero. Is this fixed by commit >>>> 3644e2d2dda78e21edd8f5415b6d7ab03f5f54f3 >>>> >>> Toralf, can you test with 5.11-rc1 (or later)? >>> >>> thanks. >> >> My plan was to apply that commit on top of the upcoming 5.10.4 and test >> that, just waiting in moment for Greg to release the stable version. >> > I commit 3644e2d2dda on top of 5.10.4 at my server - no issue so far. I > did NOT patched my desktop (same stable hardened Gentoo Linux, same > software and kernel versions) - and there it happened under 5.10.4 too: > > Jan 3 20:54:59 t44 kernel: [126159.494365] UBSAN: shift-out-of-bounds > in ./include/linux/log2.h:57:13 > Jan 3 20:54:59 t44 kernel: [126159.494371] shift exponent 64 is too > large for 64-bit type 'long unsigned int' > Jan 3 20:54:59 t44 kernel: [126159.494378] CPU: 0 PID: 16651 Comm: cc1 > Tainted: G W T 5.10.4 #5 > Jan 3 20:54:59 t44 kernel: [126159.494381] Hardware name: LENOVO > 20AQCTO1WW/20AQCTO1WW, BIOS GJETA4WW (2.54 ) 03/27/2020 > Jan 3 20:54:59 t44 kernel: [126159.494383] Call Trace: > Jan 3 20:54:59 t44 kernel: [126159.494397] dump_stack+0x57/0x6a > Jan 3 20:54:59 t44 kernel: [126159.494402] ubsan_epilogue+0x5/0x40 > Jan 3 20:54:59 t44 kernel: [126159.494408] > __ubsan_handle_shift_out_of_bounds.cold+0x61/0x10e > Jan 3 20:54:59 t44 kernel: [126159.494419] > ondemand_readahead.cold+0x16/0x21 > Jan 3 20:54:59 t44 kernel: [126159.494427] > generic_file_buffered_read+0x43d/0x880 > Jan 3 20:54:59 t44 kernel: [126159.494437] new_sync_read+0x15d/0x1f0 > Jan 3 20:54:59 t44 kernel: [126159.494442] vfs_read+0xf5/0x190 > Jan 3 20:54:59 t44 kernel: [126159.494447] ksys_read+0x65/0xe0 > Jan 3 20:54:59 t44 kernel: [126159.494453] do_syscall_64+0x33/0x40 > Jan 3 20:54:59 t44 kernel: [126159.494460] > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > Jan 3 20:54:59 t44 kernel: [126159.494466] RIP: 0033:0x7feace476dfe > Jan 3 20:54:59 t44 kernel: [126159.494472] Code: c0 e9 c6 fe ff ff 50 > 48 8d 3d de d6 09 00 e8 89 e4 01 00 66 0f 1f 84 00 00 00 00 00 64 8b 04 > 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 66 0f 1f > 84 00 00 00 00 00 48 83 ec 28 > Jan 3 20:54:59 t44 kernel: [126159.494476] RSP: 002b:00007ffe122f4318 > EFLAGS: 00000246 ORIG_RAX: 0000000000000000 > Jan 3 20:54:59 t44 kernel: [126159.494483] RAX: ffffffffffffffda RBX: > 0000000000000000 RCX: 00007feace476dfe > Jan 3 20:54:59 t44 kernel: [126159.494486] RDX: 0000000000000000 RSI: > 00000000047971a0 RDI: 0000000000000008 > Jan 3 20:54:59 t44 kernel: [126159.494489] RBP: 00000000047ba600 R08: > 00000000047971a0 R09: 000000000470d010 > Jan 3 20:54:59 t44 kernel: [126159.494492] R10: 00007feace543a00 R11: > 0000000000000246 R12: 0000000004721610 > Jan 3 20:54:59 t44 kernel: [126159.494495] R13: 00000000047971a0 R14: > 0000000000000000 R15: 0000000000000000 > Jan 3 20:54:59 t44 kernel: [126159.494499] > ================================================================================ OK, thanks for testing that commit and letting us know. -- ~Randy
