CVE-2023-52699 – sysv: don't call sb_bread() with pointers_lock held
https://notcve.org/view.php?id=CVE-2023-52699
In the Linux kernel, the following vulnerability has been resolved: sysv: don't call sb_bread() with pointers_lock held syzbot is reporting sleep in atomic context in SysV filesystem [1], for sb_bread() is called with rw_spinlock held. A "write_lock(&pointers_lock) => read_lock(&pointers_lock) deadlock" bug and a "sb_bread() with write_lock(&pointers_lock)" bug were introduced by "Replace BKL for chain locking with sysvfs-private rwlock" in Linux 2.5.12. Then, "[PATCH] err1-40: sysvfs locking fix" in Linux 2.6.8 fixed the former bug by moving pointers_lock lock to the callers, but instead introduced a "sb_bread() with read_lock(&pointers_lock)" bug (which made this problem easier to hit). Al Viro suggested that why not to do like get_branch()/get_block()/ find_shared() in Minix filesystem does. And doing like that is almost a revert of "[PATCH] err1-40: sysvfs locking fix" except that get_branch() from with find_shared() is called without write_lock(&pointers_lock). En el kernel de Linux, se resolvió la siguiente vulnerabilidad: sysv: no llame a sb_bread() con pointers_lock retenido syzbot informa suspensión en contexto atómico en el sistema de archivos SysV [1], porque sb_bread() se llama con rw_spinlock retenido. Un error "write_lock(&pointers_lock) => read_lock(&pointers_lock) deadlock" y un error "sb_bread() with write_lock(&pointers_lock)" fueron introducidos por "Reemplazar BKL para bloqueo de cadena con sysvfs-private rwlock" en Linux 2.5.12. Luego, "[PATCH] err1-40: corrección de bloqueo de sysvfs" en Linux 2.6.8 solucionó el error anterior moviendo el bloqueo pointers_lock a las personas que llaman, pero en su lugar introdujo un error "sb_bread() con read_lock(&pointers_lock)" (que hizo que esto problema más fácil de abordar). • https://git.kernel.org/stable/c/13b33feb2ebddc2b1aa607f553566b18a4af1d76 https://git.kernel.org/stable/c/1b4fe801b5bedec2b622ddb18e5c9bf26c63d79f https://git.kernel.org/stable/c/674c1c4229e743070e09db63a23442950ff000d1 https://git.kernel.org/stable/c/fd203d2c671bdee9ab77090ff394d3b71b627927 https://git.kernel.org/stable/c/53cb1e52c9db618c08335984d1ca80db220ccf09 https://git.kernel.org/stable/c/89e8524135a3902e7563a5a59b7b5ec1bf4904ac https://git.kernel.org/stable/c/a69224223746ab96d43e5db9d22d136827b7e2d3 https://git.kernel.org/stable/c/f123dc86388cb669c3d6322702dc441ab •
CVE-2024-35878 – of: module: prevent NULL pointer dereference in vsnprintf()
https://notcve.org/view.php?id=CVE-2024-35878
In the Linux kernel, the following vulnerability has been resolved: of: module: prevent NULL pointer dereference in vsnprintf() In of_modalias(), we can get passed the str and len parameters which would cause a kernel oops in vsnprintf() since it only allows passing a NULL ptr when the length is also 0. Also, we need to filter out the negative values of the len parameter as these will result in a really huge buffer since snprintf() takes size_t parameter while ours is ssize_t... Found by Linux Verification Center (linuxtesting.org) with the Svace static analysis tool. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: de: módulo: evita la desreferencia del puntero NULL en vsnprintf() En of_modalias(), podemos pasar los parámetros str y len que provocarían un kernel ups en vsnprintf() ya que solo permite pasar un ptr NULL cuando la longitud también es 0. Además, necesitamos filtrar los valores negativos del parámetro len ya que estos darán como resultado un búfer realmente enorme ya que snprintf() toma el parámetro size_t mientras que el nuestro es ssize_t... Encontrado por el Centro de verificación de Linux (linuxtesting.org) con la herramienta de análisis estático Svace. • https://git.kernel.org/stable/c/e4a449368a2ce6d57a775d0ead27fc07f5a86e5b https://git.kernel.org/stable/c/544561dc56f7e69a053c25e11e6170f48bb97898 https://git.kernel.org/stable/c/a1aa5390cc912934fee76ce80af5f940452fa987 https://access.redhat.com/security/cve/CVE-2024-35878 https://bugzilla.redhat.com/show_bug.cgi?id=2281718 • CWE-476: NULL Pointer Dereference •
CVE-2024-35875 – x86/coco: Require seeding RNG with RDRAND on CoCo systems
https://notcve.org/view.php?id=CVE-2024-35875
In the Linux kernel, the following vulnerability has been resolved: x86/coco: Require seeding RNG with RDRAND on CoCo systems There are few uses of CoCo that don't rely on working cryptography and hence a working RNG. Unfortunately, the CoCo threat model means that the VM host cannot be trusted and may actively work against guests to extract secrets or manipulate computation. Since a malicious host can modify or observe nearly all inputs to guests, the only remaining source of entropy for CoCo guests is RDRAND. If RDRAND is broken -- due to CPU hardware fault -- the RNG as a whole is meant to gracefully continue on gathering entropy from other sources, but since there aren't other sources on CoCo, this is catastrophic. This is mostly a concern at boot time when initially seeding the RNG, as after that the consequences of a broken RDRAND are much more theoretical. So, try at boot to seed the RNG using 256 bits of RDRAND output. If this fails, panic(). This will also trigger if the system is booted without RDRAND, as RDRAND is essential for a safe CoCo boot. Add this deliberately to be "just a CoCo x86 driver feature" and not part of the RNG itself. • https://git.kernel.org/stable/c/22943e4fe4b3a2dcbadc3d38d5bf840bbdbfe374 https://git.kernel.org/stable/c/453b5f2dec276c1bb4ea078bf8c0da57ee4627e5 https://git.kernel.org/stable/c/08044b08b37528b82f70a87576c692b4e4b7716e https://git.kernel.org/stable/c/99485c4c026f024e7cb82da84c7951dbe3deb584 https://access.redhat.com/security/cve/CVE-2024-35875 https://bugzilla.redhat.com/show_bug.cgi?id=2281727 •
CVE-2024-35870 – smb: client: fix UAF in smb2_reconnect_server()
https://notcve.org/view.php?id=CVE-2024-35870
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix UAF in smb2_reconnect_server() The UAF bug is due to smb2_reconnect_server() accessing a session that is already being teared down by another thread that is executing __cifs_put_smb_ses(). This can happen when (a) the client has connection to the server but no session or (b) another thread ends up setting @ses->ses_status again to something different than SES_EXITING. To fix this, we need to make sure to unconditionally set @ses->ses_status to SES_EXITING and prevent any other threads from setting a new status while we're still tearing it down. The following can be reproduced by adding some delay to right after the ipc is freed in __cifs_put_smb_ses() - which will give smb2_reconnect_server() worker a chance to run and then accessing @ses->ipc: kinit ... mount.cifs //srv/share /mnt/1 -o sec=krb5,nohandlecache,echo_interval=10 [disconnect srv] ls /mnt/1 &>/dev/null sleep 30 kdestroy [reconnect srv] sleep 10 umount /mnt/1 ... CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed CIFS: VFS: \\srv Send error in SessSetup = -126 CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed CIFS: VFS: \\srv Send error in SessSetup = -126 general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 6.9.0-rc2 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39 04/01/2014 Workqueue: cifsiod smb2_reconnect_server [cifs] RIP: 0010:__list_del_entry_valid_or_report+0x33/0xf0 Code: 4f 08 48 85 d2 74 42 48 85 c9 74 59 48 b8 00 01 00 00 00 00 ad de 48 39 c2 74 61 48 b8 22 01 00 00 00 00 74 69 <48> 8b 01 48 39 f8 75 7b 48 8b 72 08 48 39 c6 0f 85 88 00 00 00 b8 RSP: 0018:ffffc900001bfd70 EFLAGS: 00010a83 RAX: dead000000000122 RBX: ffff88810da53838 RCX: 6b6b6b6b6b6b6b6b RDX: 6b6b6b6b6b6b6b6b RSI: ffffffffc02f6878 RDI: ffff88810da53800 RBP: ffff88810da53800 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88810c064000 R13: 0000000000000001 R14: ffff88810c064000 R15: ffff8881039cc000 FS: 0000000000000000(0000) GS:ffff888157c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe3728b1000 CR3: 000000010caa4000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: <TASK> ? die_addr+0x36/0x90 ? exc_general_protection+0x1c1/0x3f0 ? asm_exc_general_protection+0x26/0x30 ? • https://git.kernel.org/stable/c/6202996a1c1887e83d0b3b0fcd86d0e5e6910ea0 https://git.kernel.org/stable/c/45f2beda1f1bc3d962ec07db1ccc3197c25499a5 https://git.kernel.org/stable/c/24a9799aa8efecd0eb55a75e35f9d8e6400063aa https://access.redhat.com/security/cve/CVE-2024-35870 https://bugzilla.redhat.com/show_bug.cgi?id=2281740 • CWE-416: Use After Free •
CVE-2024-35869 – smb: client: guarantee refcounted children from parent session
https://notcve.org/view.php?id=CVE-2024-35869
In the Linux kernel, the following vulnerability has been resolved: smb: client: guarantee refcounted children from parent session Avoid potential use-after-free bugs when walking DFS referrals, mounting and performing DFS failover by ensuring that all children from parent @tcon->ses are also refcounted. They're all needed across the entire DFS mount. Get rid of @tcon->dfs_ses_list while we're at it, too. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: smb: cliente: garantiza que los hijos recontados desde la sesión principal Evite posibles errores de use after free al recorrer referencias DFS, montar y realizar la conmutación por error de DFS asegurándose de que todos los hijos del padre @tcon- >ses también se cuentan nuevamente. Todos son necesarios en todo el montaje DFS. • https://git.kernel.org/stable/c/645f332c6b63499cc76197f9b6bffcc659ba64cc https://git.kernel.org/stable/c/e1db9ae87b7148c021daee1fcc4bc71b2ac58a79 https://git.kernel.org/stable/c/062a7f0ff46eb57aff526897bd2bebfdb1d3046a https://access.redhat.com/security/cve/CVE-2024-35869 https://bugzilla.redhat.com/show_bug.cgi?id=2281742 • CWE-416: Use After Free •