bisecting fixing commit since d2b6f8a179194de0ffc4886ffc2c4358d86047b8
building syzkaller on bc5434be1a615eca6d901c20b026712bd9697fd4
testing commit d2b6f8a179194de0ffc4886ffc2c4358d86047b8 with gcc (GCC) 10.2.1 20210217
kernel signature: 3c04afd770a2f1f821894d330f2526e57d5fac52539e0a87b640264acd6602bf
run #0: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #1: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #2: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #3: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #4: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #5: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #6: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #7: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #8: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #9: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #10: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #11: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #12: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #13: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #14: OK
run #15: OK
run #16: OK
run #17: OK
run #18: OK
run #19: OK
testing current HEAD 7fef2edf7cc753b51f7ccc74993971b0a9c81eca
testing commit 7fef2edf7cc753b51f7ccc74993971b0a9c81eca with gcc (GCC) 10.2.1 20210217
kernel signature: 158aec30aa4183d5cad4c7b3491c0c5e5a4a6b128cb0a20f56357d6a3ae0850f
run #0: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #1: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #2: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #3: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #4: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #5: crashed: BUG: sleeping function called from invalid context in lock_sock_nested
run #6: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #7: crashed: UBSAN: shift-out-of-bounds in do_mpage_readpage
run #8: OK
run #9: OK
revisions tested: 2, total time: 34m21.553312884s (build: 14m59.783818305s, test: 18m46.376901771s)
the crash still happens on HEAD
commit msg: sd: don't mess with SD_MINORS for CONFIG_DEBUG_BLOCK_EXT_DEVT
crash: UBSAN: shift-out-of-bounds in do_mpage_readpage
================================================================================
UBSAN: shift-out-of-bounds in fs/mpage.c:189:40
shift exponent 4294967279 is too large for 64-bit type 'long long unsigned int'
CPU: 0 PID: 10194 Comm: systemd-udevd Not tainted 5.14.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x57/0x7d lib/dump_stack.c:105
 ubsan_epilogue+0x5/0x40 lib/ubsan.c:148
 __ubsan_handle_shift_out_of_bounds.cold+0x61/0xe9 lib/ubsan.c:327
 do_mpage_readpage.cold+0xb8/0x299 fs/mpage.c:189
 mpage_readahead+0x2c0/0x6c0 fs/mpage.c:389
 read_pages+0x1b0/0x7c0 mm/readahead.c:130
 page_cache_ra_unbounded+0x456/0x790 mm/readahead.c:238
 do_page_cache_ra mm/readahead.c:267 [inline]
 force_page_cache_ra+0x301/0x530 mm/readahead.c:299
 page_cache_sync_readahead include/linux/pagemap.h:884 [inline]
 filemap_get_pages+0x258/0x1420 mm/filemap.c:2467
 filemap_read+0x261/0xb90 mm/filemap.c:2550
 blkdev_read_iter+0xfb/0x180 fs/block_dev.c:1669
 call_read_iter include/linux/fs.h:2108 [inline]
 new_sync_read+0x35a/0x5f0 fs/read_write.c:415
 vfs_read+0x264/0x470 fs/read_write.c:496
 ksys_read+0xf4/0x1d0 fs/read_write.c:634
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fb6fbf09210
Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 c1 20 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24
RSP: 002b:00007fffbd0399c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 000055dce34f11c0 RCX: 00007fb6fbf09210
RDX: 0000000000000400 RSI: 000055dce34f11e8 RDI: 000000000000000f
RBP: 000055dce34f7b40 R08: 00007fb6fbef4168 R09: 0000000000000430
R10: 000000000000006d R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000400 R14: 000055dce34f7b90 R15: 0000000000000400
================================================================================