bisecting fixing commit since f8ad8187c3b536ee2b10502a8340c014204a1af0 building syzkaller on 52e3731913ab2677be27c29ed8142b04e8f28521 testing commit f8ad8187c3b536ee2b10502a8340c014204a1af0 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.1 kernel signature: 1ae4ca6c61b7517e1ab76ca2845f8b8eeb14eed2597d2acd10ce9ac3edf5a682 run #0: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #1: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #2: crashed: KASAN: out-of-bounds Read in ext4_xattr_set_entry run #3: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #4: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #5: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #6: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #7: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #8: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #9: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #10: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #11: crashed: KASAN: out-of-bounds Read in ext4_xattr_set_entry run #12: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #13: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #14: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #15: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #16: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #17: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #18: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #19: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry testing current HEAD e22ce8eb631bdc47a4a4ea7ecf4e4ba499db4f93 testing commit e22ce8eb631bdc47a4a4ea7ecf4e4ba499db4f93 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.1 kernel signature: 323db7065c5a47e92f6d833b1162225960ab0efac88f95a6c2b0853029ac443d run #0: boot failed: create image operation failed: &{Code:ZONE_RESOURCE_POOL_EXHAUSTED_WITH_DETAILS Location: Message:The zone 'projects/syzkaller/zones/us-central1-c' does not have enough resources available to fulfill the request. '(resource type:compute)'. ForceSendFields:[] NullFields:[]}. run #1: boot failed: create image operation failed: &{Code:ZONE_RESOURCE_POOL_EXHAUSTED_WITH_DETAILS Location: Message:The zone 'projects/syzkaller/zones/us-central1-c' does not have enough resources available to fulfill the request. '(resource type:compute)'. ForceSendFields:[] NullFields:[]}. run #2: boot failed: create image operation failed: &{Code:ZONE_RESOURCE_POOL_EXHAUSTED_WITH_DETAILS Location: Message:The zone 'projects/syzkaller/zones/us-central1-c' does not have enough resources available to fulfill the request. '(resource type:compute)'. ForceSendFields:[] NullFields:[]}. run #3: boot failed: create image operation failed: &{Code:ZONE_RESOURCE_POOL_EXHAUSTED_WITH_DETAILS Location: Message:The zone 'projects/syzkaller/zones/us-central1-c' does not have enough resources available to fulfill the request. '(resource type:compute)'. ForceSendFields:[] NullFields:[]}. run #4: boot failed: create image operation failed: &{Code:ZONE_RESOURCE_POOL_EXHAUSTED_WITH_DETAILS Location: Message:The zone 'projects/syzkaller/zones/us-central1-c' does not have enough resources available to fulfill the request. '(resource type:compute)'. ForceSendFields:[] NullFields:[]}. run #5: boot failed: create image operation failed: &{Code:ZONE_RESOURCE_POOL_EXHAUSTED_WITH_DETAILS Location: Message:The zone 'projects/syzkaller/zones/us-central1-c' does not have enough resources available to fulfill the request. '(resource type:compute)'. ForceSendFields:[] NullFields:[]}. run #6: boot failed: create image operation failed: &{Code:ZONE_RESOURCE_POOL_EXHAUSTED_WITH_DETAILS Location: Message:The zone 'projects/syzkaller/zones/us-central1-c' does not have enough resources available to fulfill the request. '(resource type:compute)'. ForceSendFields:[] NullFields:[]}. run #7: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #8: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry run #9: crashed: KASAN: use-after-free Read in ext4_xattr_set_entry revisions tested: 2, total time: 18m34.796259239s (build: 11m23.342301599s, test: 6m24.065091259s) the crash still happens on HEAD commit msg: Linux 5.14-rc7 crash: KASAN: use-after-free Read in ext4_xattr_set_entry ================================================================== BUG: KASAN: use-after-free in ext4_xattr_set_entry+0xc14/0x3780 fs/ext4/xattr.c:1589 Read of size 4 at addr ffff888040633004 by task syz-executor.4/10479 CPU: 1 PID: 10479 Comm: syz-executor.4 Not tainted 5.14.0-rc7-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+0x45/0x59 lib/dump_stack.c:105 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:436 ext4_xattr_set_entry+0xc14/0x3780 fs/ext4/xattr.c:1589 ext4_xattr_ibody_set+0x60/0x260 fs/ext4/xattr.c:2203 ext4_xattr_set_handle+0x71c/0x10e0 fs/ext4/xattr.c:2360 ext4_xattr_set+0x11d/0x2c0 fs/ext4/xattr.c:2473 __vfs_setxattr+0xdb/0x130 fs/xattr.c:180 __vfs_setxattr_noperm+0xee/0x480 fs/xattr.c:214 vfs_setxattr+0x111/0x2d0 fs/xattr.c:301 setxattr+0x157/0x260 fs/xattr.c:575 path_setxattr+0x13c/0x170 fs/xattr.c:595 __do_sys_setxattr fs/xattr.c:611 [inline] __se_sys_setxattr fs/xattr.c:607 [inline] __x64_sys_setxattr+0xbb/0x150 fs/xattr.c:607 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: 0033:0x465b09 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6146d82188 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465b09 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000020000100 RBP: 00000000004b069f R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff89ac157f R14: 00007f6146d82300 R15: 0000000000022000 The buggy address belongs to the page: page:000000009ae77f59 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x40633 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea000101ef48 ffffea00010f1708 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888040632f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888040632f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888040633000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888040633080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888040633100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================