jfs: fix uninitialized waitqueue in transaction manager

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The transaction manager initialization in txInit() was not properly
initializing TxBlock[0].waitor waitqueue, causing a crash when
txEnd(0) is called on read-only filesystems.

When a filesystem is mounted read-only, txBegin() returns tid=0 to
indicate no transaction. However, txEnd(0) still gets called and
tries to access TxBlock[0].waitor via tid_to_tblock(0), but this
waitqueue was never initialized because the initialization loop
started at index 1 instead of 0.

This causes a 'non-static key' lockdep warning and system crash:
  INFO: trying to register non-static key in txEnd

Fix by ensuring all transaction blocks including TxBlock[0] have
their waitqueues properly initialized during txInit().

Reported-by: syzbot+c4f3462d8b2ad7977bea@syzkaller.appspotmail.com

Signed-off-by: Shaurya Rane <ssrane_b23@ee.vjti.ac.in>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>

...

This commit is contained in:

Shaurya Rane 2025-08-25 01:43:32 +05:30 • committed by Dave Kleikamp

parent 7a5aa54fba

commit 300b072df7

1 changed files with 5 additions and 4 deletions

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fs/jfs/jfs_txnmgr.c

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