Thadeu Lima de Souza CascardoandGreg Kroah-Hartman c7837e2c96 dlm: prevent NPD when writing a positive value to event_done ...

commit 8e2bad543e upstream.

do_uevent returns the value written to event_done. In case it is a
positive value, new_lockspace would undo all the work, and lockspace
would not be set. __dlm_new_lockspace, however, would treat that
positive value as a success due to commit 8511a2728a ("dlm: fix use
count with multiple joins").

Down the line, device_create_lockspace would pass that NULL lockspace to
dlm_find_lockspace_local, leading to a NULL pointer dereference.

Treating such positive values as successes prevents the problem. Given
this has been broken for so long, this is unlikely to break userspace
expectations.

Fixes: 8511a2728a ("dlm: fix use count with multiple joins")
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Nazar Kalashnikov <nazarkalashnikov0@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2026-07-04 13:41:29 +02:00

..

ast.c

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ast.h

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config.c

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config.h

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debug_fs.c

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dir.c

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dir.h

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dlm_internal.h

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Kconfig

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lock.c

dlm: fix possible lkb_resource null dereference

2026-03-25 11:03:25 +01:00

lock.h

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lockspace.c

dlm: prevent NPD when writing a positive value to event_done

2026-07-04 13:41:29 +02:00

lockspace.h

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lowcomms.c

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lowcomms.h

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lvb_table.h

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main.c

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Makefile

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member.c

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member.h

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memory.c

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memory.h

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midcomms.c

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midcomms.h

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netlink.c

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plock.c

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rcom.c

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rcom.h

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recover.c

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recover.h

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recoverd.c

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recoverd.h

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requestqueue.c

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requestqueue.h

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user.c

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user.h

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util.c

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util.h

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