[syzbot] Monthly ext4 report (Oct 2025)

From: syzbot

Date: Wed Oct 29 2025 - 05:02:29 EST


Hello ext4 maintainers/developers,

This is a 31-day syzbot report for the ext4 subsystem.
All related reports/information can be found at:
https://syzkaller.appspot.com/upstream/s/ext4

During the period, 3 new issues were detected and 1 were fixed.
In total, 50 issues are still open and 163 have already been fixed.

Some of the still happening issues:

Ref Crashes Repro Title
<1> 3903 Yes KASAN: out-of-bounds Read in ext4_xattr_set_entry
https://syzkaller.appspot.com/bug?extid=f792df426ff0f5ceb8d1
<2> 2813 Yes kernel BUG in ext4_do_writepages
https://syzkaller.appspot.com/bug?extid=d1da16f03614058fdc48
<3> 2779 Yes INFO: task hung in sync_inodes_sb (5)
https://syzkaller.appspot.com/bug?extid=30476ec1b6dc84471133
<4> 989 Yes WARNING in ext4_xattr_inode_lookup_create
https://syzkaller.appspot.com/bug?extid=fe42a669c87e4a980051
<5> 572 No KCSAN: data-race in generic_buffers_fsync_noflush / writeback_single_inode (3)
https://syzkaller.appspot.com/bug?extid=35257a2200785ea628f5
<6> 493 Yes possible deadlock in ext4_writepages (2)
https://syzkaller.appspot.com/bug?extid=eb5b4ef634a018917f3c
<7> 269 Yes INFO: task hung in do_renameat2 (2)
https://syzkaller.appspot.com/bug?extid=39a12f7473ed8066d2ca
<8> 266 Yes possible deadlock in ext4_xattr_inode_lookup_create
https://syzkaller.appspot.com/bug?extid=d91a6e2efb07bd3354e9
<9> 168 Yes kernel BUG in ext4_mb_use_inode_pa (2)
https://syzkaller.appspot.com/bug?extid=d79019213609e7056a19
<10> 140 Yes KASAN: use-after-free Read in ext4_find_extent (4)
https://syzkaller.appspot.com/bug?extid=ee60e584b5c6bb229126

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