Vulnerabilidad en kernel de Linux (CVE-2024-56743)

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: nfs_common: no debe mantener la RCU mientras se llama a nfsd_file_put_local Mueva la retención de la RCU de nfs_to_nfsd_file_put_local a nfs_to_nfsd_net_put. Es la llamada a nfs_to->nfsd_serv_put la que requiere la RCU de todos modos (las puts para nfsd_file y netns se combinaron para evitar una referencia indirecta adicional, pero esa microoptimización ahora no es posible). Esto corrige xfstests generic/013 y su activación: "¡Cambio de contexto voluntario dentro de la sección crítica del lado de lectura de RCU!" [ 143.545738] Seguimiento de llamadas: [ 143.546206] [ 143.546625] ? asm_exc_invalid_op+0x1f/0x30 [ 143.551736] ? rcu_note_context_switch+0x496/0x5d0 [ 143.552634] ? wakeup_preempt+0x62/0x70 [ 143.553358] ? __schedule+0xaa/0x1380 [ 143.554025] ? _raw_spin_unlock_irqrestore+0x12/0x40 [ 143.554958] ? try_to_wake_up+0x1fe/0x6b0 [ 143.555715] ? xfs_efi_item_format+0x50/0xc0 [xfs] [ 143.559894] lectura_bajada+0x4e/0xb0 [ 143.560519] xlog_cil_commit+0x1b2/0xbc0 [xfs] [ 143.561460] ? xfs_inode_item_precommit+0xc7/0x220 [xfs] [ 143.563309] ? xfs_trans_run_precommits+0x69/0xd0 [xfs] [ 143.564394] __xfs_trans_commit+0xb5/0x330 [xfs] [ 143.565367] xfs_trans_roll+0x48/0xc0 [xfs] [ 143.566262] xfs_defer_trans_roll+0x57/0x100 [xfs] [ 143.567278] xfs_defer_finish_noroll+0x27a/0x490 [xfs] [ 143.568342] xfs_defer_finish+0x1a/0x80 [xfs] [ 143.569267] xfs_bunmapi_range+0x4d/0xb0 [xfs] [ 143.570208] xfs_itruncate_extents_flags+0x13d/0x230 [xfs] [ 143.571353] xfs_free_eofblocks+0x12e/0x190 [xfs] [ 143.572359] xfs_file_release+0x12d/0x140 [xfs] [ 143.573324] __fput+0xe8/0x2d0 [ 143.573922] __fput_sync+0x1d/0x30 [ 143.574574] nfsd_filp_close+0x33/0x60 [nfsd] [ 143.575430] nfsd_file_free+0x96/0x150 [nfsd] [ 143.576274] nfsd_file_put+0xf7/0x1a0 [nfsd] [ 143.577104] nfsd_file_put_local+0x18/0x30 [nfsd] [ 143.578070] nfs_close_local_fh+0x101/0x110 [nfs_localio] [ 143.579079] __put_nfs_open_context+0xc9/0x180 [nfs] [ 143.580031] nfs_file_clear_open_context+0x4a/0x60 [nfs] [ 143.581038] liberación_archivo_nfs+0x3e/0x60 [nfs] [ 143.581879] __fput+0xe8/0x2d0 [ 143.582464] __fput_sync+0x1d/0x30 [ 143.583108] __x64_sys_close+0x41/0x80 [ 143.583823] llamada_sys_x64+0x189a/0x20d0 [ 143.584552] llamada_sys_64+0x64/0x170 [ 143.585240] entrada_SYSCALL_64_después_hwframe+0x76/0x7e [ 143.586185] Descanse en paz: 0033:0x7f3c5153efd7