CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2021-46982 – f2fs: compress: fix race condition of overwrite vs truncate
https://notcve.org/view.php?id=CVE-2021-46982
In the Linux kernel, the following vulnerability has been resolved: f2fs: compress: fix race condition of overwrite vs truncate pos_fsstress testcase complains a panic as belew: ------------[ cut here ]------------ kernel BUG at fs/f2fs/compress.c:1082! invalid opcode: 0000 [#1] SMP PTI CPU: 4 PID: 2753477 Comm: kworker/u16:2 Tainted: G OE 5.12.0-rc1-custom #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 Workqueue: writeback wb_workfn (flush-252:16) RIP: 0010:prepare_compress_overwrite+0x4c0/0x760 [f2fs] Call Trace: f2fs_prepare_compress_overwrite+0x5f/0x80 [f2fs] f2fs_write_cache_pages+0x468/0x8a0 [f2fs] f2fs_write_data_pages+0x2a4/0x2f0 [f2fs] do_writepages+0x38/0xc0 __writeback_single_inode+0x44/0x2a0 writeback_sb_inodes+0x223/0x4d0 __writeback_inodes_wb+0x56/0xf0 wb_writeback+0x1dd/0x290 wb_workfn+0x309/0x500 process_one_work+0x220/0x3c0 worker_thread+0x53/0x420 kthread+0x12f/0x150 ret_from_fork+0x22/0x30 The root cause is truncate() may race with overwrite as below, so that one reference count left in page can not guarantee the page attaching in mapping tree all the time, after truncation, later find_lock_page() may return NULL pointer. - prepare_compress_overwrite - f2fs_pagecache_get_page - unlock_page - f2fs_setattr - truncate_setsize - truncate_inode_page - delete_from_page_cache - find_lock_page Fix this by avoiding referencing updated page. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: f2fs: comprimir: corregir la condición de ejecución de sobrescritura frente a truncar pos_fsstress testcase presenta un pánico como se muestra a continuación: ------------[ cortar aquí ]--- --------- ¡ERROR del kernel en fs/f2fs/compress.c:1082! código de operación no válido: 0000 [#1] SMP PTI CPU: 4 PID: 2753477 Comm: kworker/u16:2 Contaminado: G OE 5.12.0-rc1-custom #1 Nombre del hardware: PC estándar QEMU (i440FX + PIIX, 1996), BIOS 1.14.0-2 01/04/2014 Cola de trabajo: reescritura wb_workfn (flush-252:16) RIP: 0010:prepare_compress_overwrite+0x4c0/0x760 [f2fs] Seguimiento de llamadas: f2fs_prepare_compress_overwrite+0x5f/0x80 [f2fs] f2fs_write_cache_pages+ 0x468/0x8a0 [f2fs] f2fs_write_data_pages+0x2a4/0x2f0 [f2fs] do_writepages+0x38/0xc0 __writeback_single_inode+0x44/0x2a0 writeback_sb_inodes+0x223/0x4d0 __writeback_inodes_wb+0x56/0xf0 wb_writeback+0x1dd/0 x290 wb_workfn+0x309/0x500 proceso_one_work+0x220/0x3c0 trabajador_thread+0x53/ 0x420 kthread+0x12f/0x150 ret_from_fork+0x22/0x30 La causa principal es que truncate() puede correr con sobrescritura como se muestra a continuación, por lo que un recuento de referencias restante en la página no puede garantizar que la página se adjunte en el árbol de mapeo todo el tiempo, después del truncamiento, más adelante find_lock_page() puede devolver un puntero NULL. - prepare_compress_overwrite - f2fs_pagecache_get_page - unlock_page - f2fs_setattr - truncate_setsize - truncate_inode_page - delete_from_page_cache - find_lock_page Solucione este problema evitando hacer referencia a la página actualizada. • https://git.kernel.org/stable/c/4c8ff7095bef64fc47e996a938f7d57f9e077da3 https://git.kernel.org/stable/c/5639b73fd3bc6fc8ca72e3a9ac15aacaabd7ebff https://git.kernel.org/stable/c/64acb100fe3beb5d20184d0ae3307235bd3555c4 https://git.kernel.org/stable/c/936158b15e2648253afb824d252c910c496d34b5 https://git.kernel.org/stable/c/a949dc5f2c5cfe0c910b664650f45371254c0744 •
CVSS: -EPSS: 0%CPEs: 11EXPL: 0CVE-2021-46981 – nbd: Fix NULL pointer in flush_workqueue
https://notcve.org/view.php?id=CVE-2021-46981
In the Linux kernel, the following vulnerability has been resolved: nbd: Fix NULL pointer in flush_workqueue Open /dev/nbdX first, the config_refs will be 1 and the pointers in nbd_device are still null. Disconnect /dev/nbdX, then reference a null recv_workq. The protection by config_refs in nbd_genl_disconnect is useless. [ 656.366194] BUG: kernel NULL pointer dereference, address: 0000000000000020 [ 656.368943] #PF: supervisor write access in kernel mode [ 656.369844] #PF: error_code(0x0002) - not-present page [ 656.370717] PGD 10cc87067 P4D 10cc87067 PUD 1074b4067 PMD 0 [ 656.371693] Oops: 0002 [#1] SMP [ 656.372242] CPU: 5 PID: 7977 Comm: nbd-client Not tainted 5.11.0-rc5-00040-g76c057c84d28 #1 [ 656.373661] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014 [ 656.375904] RIP: 0010:mutex_lock+0x29/0x60 [ 656.376627] Code: 00 0f 1f 44 00 00 55 48 89 fd 48 83 05 6f d7 fe 08 01 e8 7a c3 ff ff 48 83 05 6a d7 fe 08 01 31 c0 65 48 8b 14 25 00 6d 01 00 <f0> 48 0f b1 55 d [ 656.378934] RSP: 0018:ffffc900005eb9b0 EFLAGS: 00010246 [ 656.379350] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 656.379915] RDX: ffff888104cf2600 RSI: ffffffffaae8f452 RDI: 0000000000000020 [ 656.380473] RBP: 0000000000000020 R08: 0000000000000000 R09: ffff88813bd6b318 [ 656.381039] R10: 00000000000000c7 R11: fefefefefefefeff R12: ffff888102710b40 [ 656.381599] R13: ffffc900005eb9e0 R14: ffffffffb2930680 R15: ffff88810770ef00 [ 656.382166] FS: 00007fdf117ebb40(0000) GS:ffff88813bd40000(0000) knlGS:0000000000000000 [ 656.382806] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 656.383261] CR2: 0000000000000020 CR3: 0000000100c84000 CR4: 00000000000006e0 [ 656.383819] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 656.384370] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 656.384927] Call Trace: [ 656.385111] flush_workqueue+0x92/0x6c0 [ 656.385395] nbd_disconnect_and_put+0x81/0xd0 [ 656.385716] nbd_genl_disconnect+0x125/0x2a0 [ 656.386034] genl_family_rcv_msg_doit.isra.0+0x102/0x1b0 [ 656.386422] genl_rcv_msg+0xfc/0x2b0 [ 656.386685] ? nbd_ioctl+0x490/0x490 [ 656.386954] ? • https://git.kernel.org/stable/c/e9e006f5fcf2bab59149cb38a48a4817c1b538b4 https://git.kernel.org/stable/c/0b584bf573ae59021069c056c22d65d5721910cb https://git.kernel.org/stable/c/d1db913b044f0a0693d8ee283d26b81d536efcd5 https://git.kernel.org/stable/c/9f0f39c92e4f50189155dfb13bb5524372e40eba https://git.kernel.org/stable/c/e83a26a49356a3dbd4f54102abe17fc594643698 https://git.kernel.org/stable/c/92ec11cccb7fc14331e000ab2337f60aa433433e https://git.kernel.org/stable/c/b3ead320dce6c7d7206103deca766b317591c286 https://git.kernel.org/stable/c/1c4962df938891af9ab4775f5224ef860 •
CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2021-46977 – KVM: VMX: Disable preemption when probing user return MSRs
https://notcve.org/view.php?id=CVE-2021-46977
In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Disable preemption when probing user return MSRs Disable preemption when probing a user return MSR via RDSMR/WRMSR. If the MSR holds a different value per logical CPU, the WRMSR could corrupt the host's value if KVM is preempted between the RDMSR and WRMSR, and then rescheduled on a different CPU. Opportunistically land the helper in common x86, SVM will use the helper in a future commit. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: KVM: VMX: deshabilite la preferencia al sondear los MSR devueltos por el usuario. Deshabilite la preferencia al sondear el MSR devuelto por un usuario a través de RDSMR/WRMSR. Si MSR tiene un valor diferente por CPU lógica, WRMSR podría dañar el valor del host si KVM se adelanta entre RDMSR y WRMSR y luego se reprograma en una CPU diferente. • https://git.kernel.org/stable/c/4be5341026246870818e28b53202b001426a5aec https://git.kernel.org/stable/c/31f29749ee970c251b3a7e5b914108425940d089 https://git.kernel.org/stable/c/5adcdeb57007ccf8ab7ac20bf787ffb6fafb1a94 https://git.kernel.org/stable/c/e3ea1895df719c4ef87862501bb10d95f4177bed https://git.kernel.org/stable/c/5104d7ffcf24749939bea7fdb5378d186473f890 •
CVSS: -EPSS: 0%CPEs: 5EXPL: 0CVE-2020-36787 – media: aspeed: fix clock handling logic
https://notcve.org/view.php?id=CVE-2020-36787
In the Linux kernel, the following vulnerability has been resolved: media: aspeed: fix clock handling logic Video engine uses eclk and vclk for its clock sources and its reset control is coupled with eclk so the current clock enabling sequence works like below. Enable eclk De-assert Video Engine reset 10ms delay Enable vclk It introduces improper reset on the Video Engine hardware and eventually the hardware generates unexpected DMA memory transfers that can corrupt memory region in random and sporadic patterns. This issue is observed very rarely on some specific AST2500 SoCs but it causes a critical kernel panic with making a various shape of signature so it's extremely hard to debug. Moreover, the issue is observed even when the video engine is not actively used because udevd turns on the video engine hardware for a short time to make a query in every boot. To fix this issue, this commit changes the clock handling logic to make the reset de-assertion triggered after enabling both eclk and vclk. Also, it adds clk_unprepare call for a case when probe fails. clk: ast2600: fix reset settings for eclk and vclk Video engine reset setting should be coupled with eclk to match it with the setting for previous Aspeed SoCs which is defined in clk-aspeed.c since all Aspeed SoCs are sharing a single video engine driver. Also, reset bit 6 is defined as 'Video Engine' reset in datasheet so it should be de-asserted when eclk is enabled. • https://git.kernel.org/stable/c/d2b4387f3bdf016e266d23cf657465f557721488 https://git.kernel.org/stable/c/1dc1d30ac101bb8335d9852de2107af60c2580e7 https://git.kernel.org/stable/c/a59d01384c80a8a4392665802df57c3df20055f5 https://git.kernel.org/stable/c/2964c37563e86cfdc439f217eb3c5a69adfdba6a https://git.kernel.org/stable/c/75321dc8aebe3f30eff226028fe6da340fe0bf02 https://git.kernel.org/stable/c/3536169f8531c2c5b153921dc7d1ac9fd570cda7 •
CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2020-36784 – i2c: cadence: fix reference leak when pm_runtime_get_sync fails
https://notcve.org/view.php?id=CVE-2020-36784
In the Linux kernel, the following vulnerability has been resolved: i2c: cadence: fix reference leak when pm_runtime_get_sync fails The PM reference count is not expected to be incremented on return in functions cdns_i2c_master_xfer and cdns_reg_slave. However, pm_runtime_get_sync will increment pm usage counter even failed. Forgetting to putting operation will result in a reference leak here. Replace it with pm_runtime_resume_and_get to keep usage counter balanced. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: i2c: cadencia: corrige la fuga de referencia cuando falla pm_runtime_get_sync No se espera que el recuento de referencias de PM aumente al regresar en las funciones cdns_i2c_master_xfer y cdns_reg_slave. Sin embargo, pm_runtime_get_sync incrementará el contador de uso de pm incluso si falla. Olvidarse de poner en funcionamiento resultará en una fuga de referencia aquí. • https://git.kernel.org/stable/c/7fa32329ca03148fb2c07b4ef3247b8fc0488d6a https://git.kernel.org/stable/c/30410519328c94367e561fd878e5f0d3a0303585 https://git.kernel.org/stable/c/d57ff04e0ed6f3be1682ae861ead33f879225e07 https://git.kernel.org/stable/c/a45fc41beed8e0fe31864619c34aa00797fb60c1 https://git.kernel.org/stable/c/23ceb8462dc6f4b4decdb5536a7e5fc477cdf0b6 •