CVE-2024-26924 – netfilter: nft_set_pipapo: do not free live element
https://notcve.org/view.php?id=CVE-2024-26924
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_pipapo: do not free live element Pablo reports a crash with large batches of elements with a back-to-back add/remove pattern. Quoting Pablo: add_elem("00000000") timeout 100 ms ... add_elem("0000000X") timeout 100 ms del_elem("0000000X") <---------------- delete one that was just added ... add_elem("00005000") timeout 100 ms 1) nft_pipapo_remove() removes element 0000000X Then, KASAN shows a splat. Looking at the remove function there is a chance that we will drop a rule that maps to a non-deactivated element. Removal happens in two steps, first we do a lookup for key k and return the to-be-removed element and mark it as inactive in the next generation. Then, in a second step, the element gets removed from the set/map. The _remove function does not work correctly if we have more than one element that share the same key. This can happen if we insert an element into a set when the set already holds an element with same key, but the element mapping to the existing key has timed out or is not active in the next generation. In such case its possible that removal will unmap the wrong element. If this happens, we will leak the non-deactivated element, it becomes unreachable. The element that got deactivated (and will be freed later) will remain reachable in the set data structure, this can result in a crash when such an element is retrieved during lookup (stale pointer). Add a check that the fully matching key does in fact map to the element that we have marked as inactive in the deactivation step. If not, we need to continue searching. Add a bug/warn trap at the end of the function as well, the remove function must not ever be called with an invisible/unreachable/non-existent element. v2: avoid uneeded temporary variable (Stefano) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfilter: nft_set_pipapo: no liberar elemento activo Pablo informa un bloqueo con grandes lotes de elementos con un patrón de agregar/eliminar consecutivos. Citando a Pablo: add_elem("00000000") timeout 100 ms ... add_elem("0000000X") timeout 100 ms del_elem("0000000X") <---------------- elimina uno que se acaba de agregar... add_elem("00005000") tiempo de espera 100 ms 1) nft_pipapo_remove() elimina el elemento 0000000X Luego, KASAN muestra un símbolo. Al observar la función de eliminación, existe la posibilidad de que eliminemos una regla que se asigne a un elemento no desactivado. La eliminación se realiza en dos pasos: primero buscamos la clave k, devolvemos el elemento que se va a eliminar y lo marcamos como inactivo en la próxima generación. • https://git.kernel.org/stable/c/3c4287f62044a90e73a561aa05fc46e62da173da https://git.kernel.org/stable/c/e3b887a9c11caf8357a821260e095f2a694a34f2 https://git.kernel.org/stable/c/7a1679e2d9bfa3b5f8755c2c7113e54b7d42bd46 https://git.kernel.org/stable/c/41d8fdf3afaff312e17466e4ab732937738d5644 https://git.kernel.org/stable/c/ebf7c9746f073035ee26209e38c3a1170f7b349a https://git.kernel.org/stable/c/14b001ba221136c15f894577253e8db535b99487 https://git.kernel.org/stable/c/3cfc9ec039af60dbd8965ae085b2c2ccdcfbe1cc https://lists.debian.org/debian-lts-announce/2024/06/ • CWE-402: Transmission of Private Resources into a New Sphere ('Resource Leak') CWE-476: NULL Pointer Dereference •
CVE-2024-26923 – af_unix: Fix garbage collector racing against connect()
https://notcve.org/view.php?id=CVE-2024-26923
In the Linux kernel, the following vulnerability has been resolved: af_unix: Fix garbage collector racing against connect() Garbage collector does not take into account the risk of embryo getting enqueued during the garbage collection. If such embryo has a peer that carries SCM_RIGHTS, two consecutive passes of scan_children() may see a different set of children. Leading to an incorrectly elevated inflight count, and then a dangling pointer within the gc_inflight_list. sockets are AF_UNIX/SOCK_STREAM S is an unconnected socket L is a listening in-flight socket bound to addr, not in fdtable V's fd will be passed via sendmsg(), gets inflight count bumped connect(S, addr) sendmsg(S, [V]); close(V) __unix_gc() ---------------- ------------------------- ----------- NS = unix_create1() skb1 = sock_wmalloc(NS) L = unix_find_other(addr) unix_state_lock(L) unix_peer(S) = NS // V count=1 inflight=0 NS = unix_peer(S) skb2 = sock_alloc() skb_queue_tail(NS, skb2[V]) // V became in-flight // V count=2 inflight=1 close(V) // V count=1 inflight=1 // GC candidate condition met for u in gc_inflight_list: if (total_refs == inflight_refs) add u to gc_candidates // gc_candidates={L, V} for u in gc_candidates: scan_children(u, dec_inflight) // embryo (skb1) was not // reachable from L yet, so V's // inflight remains unchanged __skb_queue_tail(L, skb1) unix_state_unlock(L) for u in gc_candidates: if (u.inflight) scan_children(u, inc_inflight_move_tail) // V count=1 inflight=2 (!) If there is a GC-candidate listening socket, lock/unlock its state. This makes GC wait until the end of any ongoing connect() to that socket. • https://git.kernel.org/stable/c/1fd05ba5a2f2aa8e7b9b52ef55df850e2e7d54c9 https://git.kernel.org/stable/c/a36ae0ec2353015f0f6762e59f4c2dbc0c906423 https://git.kernel.org/stable/c/343c5372d5e17b306db5f8f3c895539b06e3177f https://git.kernel.org/stable/c/2e2a03787f4f0abc0072350654ab0ef3324d9db3 https://git.kernel.org/stable/c/e76c2678228f6aec74b305ae30c9374cc2f28a51 https://git.kernel.org/stable/c/b75722be422c276b699200de90527d01c602ea7c https://git.kernel.org/stable/c/507cc232ffe53a352847893f8177d276c3b532a9 https://git.kernel.org/stable/c/dbdf7bec5c920200077d693193f989cb1 • CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') •
CVE-2024-26922 – drm/amdgpu: validate the parameters of bo mapping operations more clearly
https://notcve.org/view.php?id=CVE-2024-26922
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: validate the parameters of bo mapping operations more clearly Verify the parameters of amdgpu_vm_bo_(map/replace_map/clearing_mappings) in one common place. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: drm/amdgpu: valide los parámetros de las operaciones de mapeo de bo con mayor claridad. Verifique los parámetros de amdgpu_vm_bo_(map/replace_map/clearing_mappings) en un lugar común. • https://git.kernel.org/stable/c/dc54d3d1744d23ed0b345fd8bc1c493b74e8df44 https://git.kernel.org/stable/c/d4da6b084f1c5625937d49bb6722c5b4aef11b8d https://git.kernel.org/stable/c/f68039375d4d6d67303674c0ab2d06b7295c0ec9 https://git.kernel.org/stable/c/1fd7db5c16028dc07b2ceec190f2e895dddb532d https://git.kernel.org/stable/c/8b12fc7b032633539acdf7864888b0ebd49e90f2 https://git.kernel.org/stable/c/212e3baccdb1939606420d88f7f52d346b49a284 https://git.kernel.org/stable/c/ef13eeca7c79136bc38e21eb67322c1cbd5c40ee https://git.kernel.org/stable/c/b1f04b9b1c5317f562a455384c5f7473e • CWE-20: Improper Input Validation •
CVE-2024-26921 – inet: inet_defrag: prevent sk release while still in use
https://notcve.org/view.php?id=CVE-2024-26921
In the Linux kernel, the following vulnerability has been resolved: inet: inet_defrag: prevent sk release while still in use ip_local_out() and other functions can pass skb->sk as function argument. If the skb is a fragment and reassembly happens before such function call returns, the sk must not be released. This affects skb fragments reassembled via netfilter or similar modules, e.g. openvswitch or ct_act.c, when run as part of tx pipeline. Eric Dumazet made an initial analysis of this bug. Quoting Eric: Calling ip_defrag() in output path is also implying skb_orphan(), which is buggy because output path relies on sk not disappearing. A relevant old patch about the issue was : 8282f27449bf ("inet: frag: Always orphan skbs inside ip_defrag()") [..] net/ipv4/ip_output.c depends on skb->sk being set, and probably to an inet socket, not an arbitrary one. If we orphan the packet in ipvlan, then downstream things like FQ packet scheduler will not work properly. We need to change ip_defrag() to only use skb_orphan() when really needed, ie whenever frag_list is going to be used. Eric suggested to stash sk in fragment queue and made an initial patch. However there is a problem with this: If skb is refragmented again right after, ip_do_fragment() will copy head->sk to the new fragments, and sets up destructor to sock_wfree. IOW, we have no choice but to fix up sk_wmem accouting to reflect the fully reassembled skb, else wmem will underflow. This change moves the orphan down into the core, to last possible moment. As ip_defrag_offset is aliased with sk_buff->sk member, we must move the offset into the FRAG_CB, else skb->sk gets clobbered. This allows to delay the orphaning long enough to learn if the skb has to be queued or if the skb is completing the reasm queue. In the former case, things work as before, skb is orphaned. This is safe because skb gets queued/stolen and won't continue past reasm engine. In the latter case, we will steal the skb->sk reference, reattach it to the head skb, and fix up wmem accouting when inet_frag inflates truesize. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: inet: inet_defrag: evita la liberación de sk mientras aún está en uso ip_local_out() y otras funciones pueden pasar skb->sk como argumento de función. Si el skb es un fragmento y el reensamblaje ocurre antes de que regrese dicha llamada a la función, el sk no debe liberarse. • https://git.kernel.org/stable/c/7026b1ddb6b8d4e6ee33dc2bd06c0ca8746fa7ab https://git.kernel.org/stable/c/1b6de5e6575b56502665c65cf93b0ae6aa0f51ab https://git.kernel.org/stable/c/9705f447bf9a6cd088300ad2c407b5e1c6591091 https://git.kernel.org/stable/c/4318608dc28ef184158b4045896740716bea23f0 https://git.kernel.org/stable/c/7d0567842b78390dd9b60f00f1d8f838d540e325 https://git.kernel.org/stable/c/f4877225313d474659ee53150ccc3d553a978727 https://git.kernel.org/stable/c/e09cbe017311508c21e0739e97198a8388b98981 https://git.kernel.org/stable/c/18685451fc4e546fc0e718580d32df3c0 • CWE-124: Buffer Underwrite ('Buffer Underflow') •
CVE-2024-26901 – do_sys_name_to_handle(): use kzalloc() to fix kernel-infoleak
https://notcve.org/view.php?id=CVE-2024-26901
In the Linux kernel, the following vulnerability has been resolved: do_sys_name_to_handle(): use kzalloc() to fix kernel-infoleak syzbot identified a kernel information leak vulnerability in do_sys_name_to_handle() and issued the following report [1]. [1] "BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline] BUG: KMSAN: kernel-infoleak in _copy_to_user+0xbc/0x100 lib/usercopy.c:40 instrument_copy_to_user include/linux/instrumented.h:114 [inline] _copy_to_user+0xbc/0x100 lib/usercopy.c:40 copy_to_user include/linux/uaccess.h:191 [inline] do_sys_name_to_handle fs/fhandle.c:73 [inline] __do_sys_name_to_handle_at fs/fhandle.c:112 [inline] __se_sys_name_to_handle_at+0x949/0xb10 fs/fhandle.c:94 __x64_sys_name_to_handle_at+0xe4/0x140 fs/fhandle.c:94 ... Uninit was created at: slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768 slab_alloc_node mm/slub.c:3478 [inline] __kmem_cache_alloc_node+0x5c9/0x970 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0x121/0x3c0 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] do_sys_name_to_handle fs/fhandle.c:39 [inline] __do_sys_name_to_handle_at fs/fhandle.c:112 [inline] __se_sys_name_to_handle_at+0x441/0xb10 fs/fhandle.c:94 __x64_sys_name_to_handle_at+0xe4/0x140 fs/fhandle.c:94 ... Bytes 18-19 of 20 are uninitialized Memory access of size 20 starts at ffff888128a46380 Data copied to user address 0000000020000240" Per Chuck Lever's suggestion, use kzalloc() instead of kmalloc() to solve the problem. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: do_sys_name_to_handle(): use kzalloc() para reparar kernel-infoleak syzbot identificó una vulnerabilidad de fuga de información del kernel en do_sys_name_to_handle() y emitió el siguiente informe [1]. [1] "ERROR: KMSAN: kernel-infoleak en instrument_copy_to_user include/linux/instrumented.h:114 [en línea] ERROR: KMSAN: kernel-infoleak en _copy_to_user+0xbc/0x100 lib/usercopy.c:40 instrument_copy_to_user include/linux/ instrumented.h:114 [en línea] _copy_to_user+0xbc/0x100 lib/usercopy.c:40 copy_to_user include/linux/uaccess.h:191 [en línea] do_sys_name_to_handle fs/fhandle.c:73 [en línea] __do_sys_name_to_handle_at fs/fhandle.c :112 [en línea] __se_sys_name_to_handle_at+0x949/0xb10 fs/fhandle.c:94 __x64_sys_name_to_handle_at+0xe4/0x140 fs/fhandle.c:94 ... Uninit se creó en: slab_post_alloc_hook+0x129/0xa70 mm/slab.h: 768 losa_alloc_nodo mm/slub.c:3478 [en línea] __kmem_cache_alloc_node+0x5c9/0x970 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1006 [en línea] __kmalloc+0x121/0x3c0 mm/slab_common.c:1020 kmalloc include/linux/ slab.h:604 [en línea] do_sys_name_to_handle fs/fhandle.c:39 [en línea] __do_sys_name_to_handle_at fs/fhandle.c:112 [en línea] __se_sys_name_to_handle_at+0x441/0xb10 fs/fhandle.c:94 _handle_at+0xe4/0x140 fs/fhandle .c:94 ... Los bytes 18-19 de 20 no están inicializados El acceso a la memoria de tamaño 20 comienza en ffff888128a46380 Datos copiados a la dirección de usuario 0000000020000240" Según la sugerencia de Chuck Lever, use kzalloc() en lugar de kmalloc() para resolver el problema. • https://git.kernel.org/stable/c/990d6c2d7aee921e3bce22b2d6a750fd552262be https://git.kernel.org/stable/c/4bac28f441e3cc9d3f1a84c8d023228a68d8a7c1 https://git.kernel.org/stable/c/772a7def9868091da3bcb0d6c6ff9f0c03d7fa8b https://git.kernel.org/stable/c/cde76b3af247f615447bcfecf610bb76c3529126 https://git.kernel.org/stable/c/423b6bdf19bbc5e1f7e7461045099917378f7e71 https://git.kernel.org/stable/c/e6450d5e46a737a008b4885aa223486113bf0ad6 https://git.kernel.org/stable/c/c1362eae861db28b1608b9dc23e49634fe87b63b https://git.kernel.org/stable/c/cba138f1ef37ec6f961baeab62f312ded • CWE-402: Transmission of Private Resources into a New Sphere ('Resource Leak') CWE-908: Use of Uninitialized Resource •