CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47131 – net/tls: Fix use-after-free after the TLS device goes down and up
https://notcve.org/view.php?id=CVE-2021-47131
In the Linux kernel, the following vulnerability has been resolved: net/tls: Fix use-after-free after the TLS device goes down and up When a netdev with active TLS offload goes down, tls_device_down is called to stop the offload and tear down the TLS context. However, the socket stays alive, and it still points to the TLS context, which is now deallocated. If a netdev goes up, while the connection is still active, and the data flow resumes after a number of TCP retransmissions, it will lead to a use-after-free of the TLS context. This commit addresses this bug by keeping the context alive until its normal destruction, and implements the necessary fallbacks, so that the connection can resume in software (non-offloaded) kTLS mode. On the TX side tls_sw_fallback is used to encrypt all packets. The RX side already has all the necessary fallbacks, because receiving non-decrypted packets is supported. The thing needed on the RX side is to block resync requests, which are normally produced after receiving non-decrypted packets. The necessary synchronization is implemented for a graceful teardown: first the fallbacks are deployed, then the driver resources are released (it used to be possible to have a tls_dev_resync after tls_dev_del). A new flag called TLS_RX_DEV_DEGRADED is added to indicate the fallback mode. • https://git.kernel.org/stable/c/e8f69799810c32dd40c6724d829eccc70baad07f https://git.kernel.org/stable/c/f1d4184f128dede82a59a841658ed40d4e6d3aa2 https://git.kernel.org/stable/c/0f1e6fe66977a864fe850522316f713d7b926fd9 https://git.kernel.org/stable/c/c55dcdd435aa6c6ad6ccac0a4c636d010ee367a4 •
CVSS: -EPSS: 0%CPEs: 8EXPL: 0CVE-2021-47122 – net: caif: fix memory leak in caif_device_notify
https://notcve.org/view.php?id=CVE-2021-47122
In the Linux kernel, the following vulnerability has been resolved: net: caif: fix memory leak in caif_device_notify In case of caif_enroll_dev() fail, allocated link_support won't be assigned to the corresponding structure. So simply free allocated pointer in case of error En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: caif: corrige la pérdida de memoria en caif_device_notify En caso de que falle caif_enroll_dev(), el link_support asignado no se asignará a la estructura correspondiente. Así que simplemente libera el puntero asignado en caso de error. • https://git.kernel.org/stable/c/7c18d2205ea76eef9674e59e1ecae4f332a53e9e https://git.kernel.org/stable/c/b042e2b2039565eb8f0eb51c14fbe1ef463c8cd8 https://git.kernel.org/stable/c/9348c1f10932f13b299cbc8b1bd5f780751fae49 https://git.kernel.org/stable/c/4bca2034b41c15b62d47a19158bb76235fd4455d https://git.kernel.org/stable/c/3be863c11cab725add9fef4237ed4e232c3fc3bb https://git.kernel.org/stable/c/f52f4fd67264c70cd0b4ba326962ebe12d9cba94 https://git.kernel.org/stable/c/af2806345a37313f01b1c9f15e046745b8ee2daa https://git.kernel.org/stable/c/6a0e317f61094d377335547e015dd2ff1 •
CVSS: -EPSS: 0%CPEs: 8EXPL: 0CVE-2021-47121 – net: caif: fix memory leak in cfusbl_device_notify
https://notcve.org/view.php?id=CVE-2021-47121
In the Linux kernel, the following vulnerability has been resolved: net: caif: fix memory leak in cfusbl_device_notify In case of caif_enroll_dev() fail, allocated link_support won't be assigned to the corresponding structure. So simply free allocated pointer in case of error. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: caif: corrige la pérdida de memoria en cfusbl_device_notify En caso de que falle caif_enroll_dev(), el link_support asignado no se asignará a la estructura correspondiente. Así que simplemente libera el puntero asignado en caso de error. • https://git.kernel.org/stable/c/7ad65bf68d705b445ef10b77ab50dab22be185ee https://git.kernel.org/stable/c/cc302e30a504e6b60a9ac8df7988646f46cd0294 https://git.kernel.org/stable/c/81afc61cb6e2b553f2c5f992fa79e0ae73857141 https://git.kernel.org/stable/c/e8b37f5009ea7095529790f022859711e6939c76 https://git.kernel.org/stable/c/9ea0ab48e755d8f29fe89eb235fb86176fdb597f https://git.kernel.org/stable/c/4d94f530cd24c85aede6e72b8923f371b45d6886 https://git.kernel.org/stable/c/46403c1f80b0d3f937ff9c4f5edc63bb64bc5051 https://git.kernel.org/stable/c/dde8686985ec24d6b00487080a906609b •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47119 – ext4: fix memory leak in ext4_fill_super
https://notcve.org/view.php?id=CVE-2021-47119
In the Linux kernel, the following vulnerability has been resolved: ext4: fix memory leak in ext4_fill_super Buffer head references must be released before calling kill_bdev(); otherwise the buffer head (and its page referenced by b_data) will not be freed by kill_bdev, and subsequently that bh will be leaked. If blocksizes differ, sb_set_blocksize() will kill current buffers and page cache by using kill_bdev(). And then super block will be reread again but using correct blocksize this time. sb_set_blocksize() didn't fully free superblock page and buffer head, and being busy, they were not freed and instead leaked. This can easily be reproduced by calling an infinite loop of: systemctl start <ext4_on_lvm>.mount, and systemctl stop <ext4_on_lvm>.mount ... since systemd creates a cgroup for each slice which it mounts, and the bh leak get amplified by a dying memory cgroup that also never gets freed, and memory consumption is much more easily noticed. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: corrige la pérdida de memoria en ext4_fill_super Las referencias del encabezado del búfer deben liberarse antes de llamar a kill_bdev(); de lo contrario, kill_bdev no liberará el encabezado del búfer (y su página a la que hace referencia b_data) y, posteriormente, se filtrará ese bh. Si los tamaños de los bloques difieren, sb_set_blocksize() eliminará los búferes actuales y el caché de la página usando kill_bdev(). Y luego el superbloque se volverá a leer, pero esta vez utilizando el tamaño de bloque correcto. sb_set_blocksize() no liberó completamente la página del superbloque y el encabezado del búfer y, al estar ocupados, no se liberaron y en su lugar se filtraron. • https://git.kernel.org/stable/c/ac27a0ec112a089f1a5102bc8dffc79c8c815571 https://git.kernel.org/stable/c/01d349a481f0591230300a9171330136f9159bcd https://git.kernel.org/stable/c/1385b23396d511d5233b8b921ac3058b3f86a5e1 https://git.kernel.org/stable/c/afd09b617db3786b6ef3dc43e28fe728cfea84df •
CVSS: 4.1EPSS: 0%CPEs: 8EXPL: 0CVE-2021-47118 – pid: take a reference when initializing `cad_pid`
https://notcve.org/view.php?id=CVE-2021-47118
In the Linux kernel, the following vulnerability has been resolved: pid: take a reference when initializing `cad_pid` During boot, kernel_init_freeable() initializes `cad_pid` to the init task's struct pid. Later on, we may change `cad_pid` via a sysctl, and when this happens proc_do_cad_pid() will increment the refcount on the new pid via get_pid(), and will decrement the refcount on the old pid via put_pid(). As we never called get_pid() when we initialized `cad_pid`, we decrement a reference we never incremented, can therefore free the init task's struct pid early. As there can be dangling references to the struct pid, we can later encounter a use-after-free (e.g. when delivering signals). This was spotted when fuzzing v5.13-rc3 with Syzkaller, but seems to have been around since the conversion of `cad_pid` to struct pid in commit 9ec52099e4b8 ("[PATCH] replace cad_pid by a struct pid") from the pre-KASAN stone age of v2.6.19. Fix this by getting a reference to the init task's struct pid when we assign it to `cad_pid`. Full KASAN splat below. ================================================================== BUG: KASAN: use-after-free in ns_of_pid include/linux/pid.h:153 [inline] BUG: KASAN: use-after-free in task_active_pid_ns+0xc0/0xc8 kernel/pid.c:509 Read of size 4 at addr ffff23794dda0004 by task syz-executor.0/273 CPU: 1 PID: 273 Comm: syz-executor.0 Not tainted 5.12.0-00001-g9aef892b2d15 #1 Hardware name: linux,dummy-virt (DT) Call trace: ns_of_pid include/linux/pid.h:153 [inline] task_active_pid_ns+0xc0/0xc8 kernel/pid.c:509 do_notify_parent+0x308/0xe60 kernel/signal.c:1950 exit_notify kernel/exit.c:682 [inline] do_exit+0x2334/0x2bd0 kernel/exit.c:845 do_group_exit+0x108/0x2c8 kernel/exit.c:922 get_signal+0x4e4/0x2a88 kernel/signal.c:2781 do_signal arch/arm64/kernel/signal.c:882 [inline] do_notify_resume+0x300/0x970 arch/arm64/kernel/signal.c:936 work_pending+0xc/0x2dc Allocated by task 0: slab_post_alloc_hook+0x50/0x5c0 mm/slab.h:516 slab_alloc_node mm/slub.c:2907 [inline] slab_alloc mm/slub.c:2915 [inline] kmem_cache_alloc+0x1f4/0x4c0 mm/slub.c:2920 alloc_pid+0xdc/0xc00 kernel/pid.c:180 copy_process+0x2794/0x5e18 kernel/fork.c:2129 kernel_clone+0x194/0x13c8 kernel/fork.c:2500 kernel_thread+0xd4/0x110 kernel/fork.c:2552 rest_init+0x44/0x4a0 init/main.c:687 arch_call_rest_init+0x1c/0x28 start_kernel+0x520/0x554 init/main.c:1064 0x0 Freed by task 270: slab_free_hook mm/slub.c:1562 [inline] slab_free_freelist_hook+0x98/0x260 mm/slub.c:1600 slab_free mm/slub.c:3161 [inline] kmem_cache_free+0x224/0x8e0 mm/slub.c:3177 put_pid.part.4+0xe0/0x1a8 kernel/pid.c:114 put_pid+0x30/0x48 kernel/pid.c:109 proc_do_cad_pid+0x190/0x1b0 kernel/sysctl.c:1401 proc_sys_call_handler+0x338/0x4b0 fs/proc/proc_sysctl.c:591 proc_sys_write+0x34/0x48 fs/proc/proc_sysctl.c:617 call_write_iter include/linux/fs.h:1977 [inline] new_sync_write+0x3ac/0x510 fs/read_write.c:518 vfs_write fs/read_write.c:605 [inline] vfs_write+0x9c4/0x1018 fs/read_write.c:585 ksys_write+0x124/0x240 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __arm64_sys_write+0x78/0xb0 fs/read_write.c:667 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall arch/arm64/kernel/syscall.c:49 [inline] el0_svc_common.constprop.1+0x16c/0x388 arch/arm64/kernel/syscall.c:129 do_el0_svc+0xf8/0x150 arch/arm64/kernel/syscall.c:168 el0_svc+0x28/0x38 arch/arm64/kernel/entry-common.c:416 el0_sync_handler+0x134/0x180 arch/arm64/kernel/entry-common.c:432 el0_sync+0x154/0x180 arch/arm64/kernel/entry.S:701 The buggy address belongs to the object at ffff23794dda0000 which belongs to the cache pid of size 224 The buggy address is located 4 bytes inside of 224-byte region [ff ---truncated--- En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: pid: toma una referencia al inicializar `cad_pid` Durante el arranque, kernel_init_freeable() inicializa `cad_pid` en la estructura pid de la tarea de inicio. • https://git.kernel.org/stable/c/9ec52099e4b8678a60e9f93e41ad87885d64f3e6 https://git.kernel.org/stable/c/764c2e892d1fe895392aff62fb353fdce43bb529 https://git.kernel.org/stable/c/f86c80515a8a3703e0ca2e56deb50fc2879c5ea4 https://git.kernel.org/stable/c/4dbd8808a591b49b717862e6e0081bcf14a87788 https://git.kernel.org/stable/c/d106f05432e60f9f62d456ef017687f5c73cb414 https://git.kernel.org/stable/c/2cd6eedfa6344f5ef5c3dac3aee57a39b5b46dff https://git.kernel.org/stable/c/7178be006d495ffb741c329012da289b62dddfe6 https://git.kernel.org/stable/c/b8ff869f20152fbe66b6c2e2715d26a2f • CWE-416: Use After Free •