CVE-2024-38596

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: af_unix: corrige ejecucións de datos en unix_release_sock/unix_stream_sendmsg Se identificó una condición de ejecución de datos en af_unix. En una ruta de datos, la función de escritura unix_release_sock() escribe atómicamente en sk->sk_shutdown usando WRITE_ONCE. Sin embargo, en el lado del lector, unix_stream_sendmsg() no lo lee atómicamente. En consecuencia, este problema está provocando que se produzca el siguiente símbolo de KCSAN: ERROR: KCSAN: data-race en unix_release_sock / unix_stream_sendmsg escribe (marcado) en 0xffff88867256ddbb de 1 byte por tarea 7270 en la CPU 28: unix_release_sock (net/unix/af_unix.c: 640) unix_release (net/unix/af_unix.c:1050) sock_close (net/socket.c:659 net/socket.c:1421) __fput (fs/file_table.c:422) __fput_sync (fs/file_table.c:508 ) __se_sys_close (fs/open.c:1559 fs/open.c:1541) __x64_sys_close (fs/open.c:1541) x64_sys_call (arch/x86/entry/syscall_64.c:33) do_syscall_64 (arch/x86/entry/ common.c:?) Entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) leído en 0xffff88867256ddbb de 1 bytes por la tarea 989 en la CPU 14: unix_stream_sendmsg (net/unix/af_unix.c:2273) __sock_sendmsg (net/socket .c:730 net/socket.c:745) ____sys_sendmsg (net/socket.c:2584) __sys_sendmmsg (net/socket.c:2638 net/socket.c:2724) __x64_sys_sendmmsg (net/socket.c:2753 net/ socket.c:2750 net/socket.c:2750) x64_sys_call (arch/x86/entry/syscall_64.c:33) do_syscall_64 (arch/x86/entry/common.c:?) Entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64 .S:130) valor cambiado: 0x01 -> 0x03 Los números de línea están relacionados con el commit dd5a440a31fa ("Linux 6.9-rc7"). El commit e1d09c2c2f57 ("af_unix: corregir ejecucións de datos alrededor de sk->sk_shutdown.") abordó un problema comparable en el pasado con respecto a sk->sk_shutdown. Sin embargo, pasó por alto resolver esta ruta de datos en particular. Este parche solo ofende la función unix_stream_sendmsg(), ya que las otras lecturas parecen estar protegidas por unix_state_lock() como se explica en

In the Linux kernel, the following vulnerability has been resolved: af_unix: Fix data races in unix_release_sock/unix_stream_sendmsg A data-race condition has been identified in af_unix. In one data path, the write function unix_release_sock() atomically writes to sk->sk_shutdown using WRITE_ONCE. However, on the reader side, unix_stream_sendmsg() does not read it atomically. Consequently, this issue is causing the following KCSAN splat to occur: BUG: KCSAN: data-race in unix_release_sock / unix_stream_sendmsg write (marked) to 0xffff88867256ddbb of 1 bytes by task 7270 on cpu 28: unix_release_sock (net/unix/af_unix.c:640) unix_release (net/unix/af_unix.c:1050) sock_close (net/socket.c:659 net/socket.c:1421) __fput (fs/file_table.c:422) __fput_sync (fs/file_table.c:508) __se_sys_close (fs/open.c:1559 fs/open.c:1541) __x64_sys_close (fs/open.c:1541) x64_sys_call (arch/x86/entry/syscall_64.c:33) do_syscall_64 (arch/x86/entry/common.c:?) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) read to 0xffff88867256ddbb of 1 bytes by task 989 on cpu 14: unix_stream_sendmsg (net/unix/af_unix.c:2273) __sock_sendmsg (net/socket.c:730 net/socket.c:745) ____sys_sendmsg (net/socket.c:2584) __sys_sendmmsg (net/socket.c:2638 net/socket.c:2724) __x64_sys_sendmmsg (net/socket.c:2753 net/socket.c:2750 net/socket.c:2750) x64_sys_call (arch/x86/entry/syscall_64.c:33) do_syscall_64 (arch/x86/entry/common.c:?) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) value changed: 0x01 -> 0x03 The line numbers are related to commit dd5a440a31fa ("Linux 6.9-rc7"). Commit e1d09c2c2f57 ("af_unix: Fix data races around sk->sk_shutdown.") addressed a comparable issue in the past regarding sk->sk_shutdown. However, it overlooked resolving this particular data path. This patch only offending unix_stream_sendmsg() function, since the other reads seem to be protected by unix_state_lock() as discussed in

Ziming Zhang discovered that the DRM driver for VMware Virtual GPU did not properly handle certain error conditions, leading to a NULL pointer dereference. A local attacker could possibly trigger this vulnerability to cause a denial of service. Gui-Dong Han discovered that the software RAID driver in the Linux kernel contained a race condition, leading to an integer overflow vulnerability. A privileged attacker could possibly use this to cause a denial of service.