CVSS 5.5 · Medium EPSS 0,14%
Kerentanan Missing Release of Memory after Effective Lifetime pada linux kernel. Skor CVSS 3.1 5.5 (Medium) menurut NVD.
In the Linux kernel, the following vulnerability has been resolved: net: fix memory leak in skb_segment_list for GRO packets When skb_segment_list() is called during packet forwarding, it handles packets that were aggregated by the GRO engine. Historically, the segmentation logic in skb_segment_list assumes that individual segments are split from a parent SKB and may need to carry their own socket memory accounting. Accordingly, the code transfers truesize from the parent to the newly created segments. Prior to commit ed4cccef64c1 ("gro: fix ownership transfer"), this truesize subtraction in skb_segment_list() was valid because fragments still carry a reference to the original socket. However, commit ed4cccef64c1 ("gro: fix ownership transfer") changed this behavior by ensuring that fraglist entries are explicitly orphaned (skb->sk = NULL) to prevent illegal orphaning later in the stack. This change meant that the entire socket memory charge remained with the head SKB, but the corresponding accounting logic in skb_segment_list() was never updated. As a result, the current code unconditionally adds each fragment's truesize to delta_truesize and subtracts it from the parent SKB. Since the fragments are no longer charged to the socket, this subtraction results in an effective under-count of memory when the head is freed. This causes sk_wmem_alloc to remain non-zero, preventing socket destruction and leading to a persistent memory leak. The leak can be observed via KMEMLEAK when tearing down the networking environment: unreferenced object 0xffff8881e6eb9100 (size 2048): comm "ping", pid 6720, jiffies 4295492526 backtrace: kmem_cache_alloc_noprof+0x5c6/0x800 sk_prot_alloc+0x5b/0x220 sk_alloc+0x35/0xa00 inet6_create.part.0+0x303/0x10d0 __sock_create+0x248/0x640 __sys_socket+0x11b/0x1d0 Since skb_segment_list() is exclusively used for SKB_GSO_FRAGLIST packets constructed by GRO, the truesize adjustment is removed. The call to skb_release_head_state() must be preserved. As documented in commit cf673ed0e057 ("net: fix fraglist segmentation reference count leak"), it is still required to correctly drop references to SKB extensions that may be overwritten during __copy_skb_header().
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| linux | linux kernel | Versi 5.15.154 hingga sebelum 5.16 |
| linux | linux kernel | Versi 6.1.85 hingga sebelum 6.1.161 |
| linux | linux kernel | Versi 6.6.26 hingga sebelum 6.6.121 |
| linux | linux kernel | Versi 6.8.5 hingga sebelum 6.9 |
| linux | linux kernel | Versi 6.9.1 hingga sebelum 6.12.66 |
| linux | linux kernel | Versi 6.13 hingga sebelum 6.18.6 |
| linux | linux kernel | Versi 6.9 |
| linux | linux kernel | Versi 6.9 rc3 |
| linux | linux kernel | Versi 6.9 rc4 |
| linux | linux kernel | Versi 6.9 rc5 |
| linux | linux kernel | Versi 6.9 rc6 |
| linux | linux kernel | Versi 6.9 rc7 |
| linux | linux kernel | Versi 6.19 rc1 |
| linux | linux kernel | Versi 6.19 rc2 |
| linux | linux kernel | Versi 6.19 rc3 |
| linux | linux kernel | Versi 6.19 rc4 |