net/mlx5: Fix rev_entry reference leak in mlx5_tc_ct_shared_counter_get()

Overview

In the Linux kernel, the following vulnerability has been resolved:

net/mlx5: Fix rev_entry reference leak in mlx5_tc_ct_shared_counter_get()

When the reverse entry is found but its counter is already being released, refcount_inc_not_zero() fails and the reference taken by mlx5_tc_ct_entry_get() is never dropped before falling through to create_counter. Drop it so the reverse entry is not kept alive forever by a shared counter lookup that did not use it.

Affected

• Linux >= 1edae2335adfa7006853e8b427f0c7c3f46b51dd < 598daa5f95883f881a54967da40ce0fdfc1fdaa8
• Linux >= 1edae2335adfa7006853e8b427f0c7c3f46b51dd < 79a3257280a335bbebbcd10d3895e8468bdcd6ae
• Linux >= 1edae2335adfa7006853e8b427f0c7c3f46b51dd < c45c997d0c27359b502587897f775c5a277f0bd4
• Linux >= 1edae2335adfa7006853e8b427f0c7c3f46b51dd < 288721013605b4e0304e10f6a087b77f71cfad11
• Linux >= 1edae2335adfa7006853e8b427f0c7c3f46b51dd < 60eab87d0a798070bf5a856b1d9e5785ce92da53
• Linux >= 1edae2335adfa7006853e8b427f0c7c3f46b51dd < 99d8dc51663747078c031acac32edc6d90c8f1f7
• Linux >= 1edae2335adfa7006853e8b427f0c7c3f46b51dd < 1f13989a0704bd98cab09f9bee63e2c8a98ad4dd
• Linux >= 1edae2335adfa7006853e8b427f0c7c3f46b51dd < 0bf6bb567f0edaa771e7dd208ef98da50e6a4485
• Linux 5.10

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.