CVE-2026-46107
Gravedad CVSS v3.1:
ALTA
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
28/05/2026
Última modificación:
30/05/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
dm-thin: fix metadata refcount underflow<br />
<br />
There&#39;s a bug in dm-thin in the function rebalance_children. If the<br />
internal btree node has one entry, the code tries to copy all btree<br />
entries from the node&#39;s child to the node itself and then decrement the<br />
child&#39;s reference count.<br />
<br />
If the child node is shared (it has reference count > 1), we won&#39;t free<br />
it, so there would be two pointers to each of the grandchildren nodes.<br />
But the reference counts of the grandchildren is not increased, thus the<br />
reference count doesn&#39;t match the number of pointers that point to the<br />
grandchildren. This results in "device mapper: space map common: unable<br />
to decrement block" errors.<br />
<br />
Fix this bug by incrementing reference counts on the grandchildren if the<br />
btree node is shared.
Impacto
Puntuación base 3.x
7.80
Gravedad 3.x
ALTA
Referencias a soluciones, herramientas e información
- https://git.kernel.org/stable/c/09a65adc7d8bbfce06392cb6d375468e2728ead5
- https://git.kernel.org/stable/c/12161e03d33afce781f68fa11cc6060538862fad
- https://git.kernel.org/stable/c/323d252a4a378834e4fe68298ca61cfc5dd3a460
- https://git.kernel.org/stable/c/5ec0debbcfd43596e32c1239e993de06a704e04c
- https://git.kernel.org/stable/c/85311a585a26640760cd0f3349ab9f2905691044



