CVE-2023-54196

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> fs/ntfs3: Fix NULL pointer dereference in &amp;#39;ni_write_inode&amp;#39;<br /> <br /> Syzbot found the following issue:<br /> Unable to handle kernel NULL pointer dereference at virtual address 0000000000000016<br /> Mem abort info:<br /> ESR = 0x0000000096000006<br /> EC = 0x25: DABT (current EL), IL = 32 bits<br /> SET = 0, FnV = 0<br /> EA = 0, S1PTW = 0<br /> FSC = 0x06: level 2 translation fault<br /> Data abort info:<br /> ISV = 0, ISS = 0x00000006<br /> CM = 0, WnR = 0<br /> user pgtable: 4k pages, 48-bit VAs, pgdp=000000010af56000<br /> [0000000000000016] pgd=08000001090da003, p4d=08000001090da003, pud=08000001090ce003, pmd=0000000000000000<br /> Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP<br /> Modules linked in:<br /> CPU: 1 PID: 3036 Comm: syz-executor206 Not tainted 6.0.0-rc6-syzkaller-17739-g16c9f284e746 #0<br /> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022<br /> pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)<br /> pc : is_rec_inuse fs/ntfs3/ntfs.h:313 [inline]<br /> pc : ni_write_inode+0xac/0x798 fs/ntfs3/frecord.c:3232<br /> lr : ni_write_inode+0xa0/0x798 fs/ntfs3/frecord.c:3226<br /> sp : ffff8000126c3800<br /> x29: ffff8000126c3860 x28: 0000000000000000 x27: ffff0000c8b02000<br /> x26: ffff0000c7502320 x25: ffff0000c7502288 x24: 0000000000000000<br /> x23: ffff80000cbec91c x22: ffff0000c8b03000 x21: ffff0000c8b02000<br /> x20: 0000000000000001 x19: ffff0000c75024d8 x18: 00000000000000c0<br /> x17: ffff80000dd1b198 x16: ffff80000db59158 x15: ffff0000c4b6b500<br /> x14: 00000000000000b8 x13: 0000000000000000 x12: ffff0000c4b6b500<br /> x11: ff80800008be1b60 x10: 0000000000000000 x9 : ffff0000c4b6b500<br /> x8 : 0000000000000000 x7 : ffff800008be1b50 x6 : 0000000000000000<br /> x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000<br /> x2 : 0000000000000008 x1 : 0000000000000001 x0 : 0000000000000000<br /> Call trace:<br /> is_rec_inuse fs/ntfs3/ntfs.h:313 [inline]<br /> ni_write_inode+0xac/0x798 fs/ntfs3/frecord.c:3232<br /> ntfs_evict_inode+0x54/0x84 fs/ntfs3/inode.c:1744<br /> evict+0xec/0x334 fs/inode.c:665<br /> iput_final fs/inode.c:1748 [inline]<br /> iput+0x2c4/0x324 fs/inode.c:1774<br /> ntfs_new_inode+0x7c/0xe0 fs/ntfs3/fsntfs.c:1660<br /> ntfs_create_inode+0x20c/0xe78 fs/ntfs3/inode.c:1278<br /> ntfs_create+0x54/0x74 fs/ntfs3/namei.c:100<br /> lookup_open fs/namei.c:3413 [inline]<br /> open_last_lookups fs/namei.c:3481 [inline]<br /> path_openat+0x804/0x11c4 fs/namei.c:3688<br /> do_filp_open+0xdc/0x1b8 fs/namei.c:3718<br /> do_sys_openat2+0xb8/0x22c fs/open.c:1311<br /> do_sys_open fs/open.c:1327 [inline]<br /> __do_sys_openat fs/open.c:1343 [inline]<br /> __se_sys_openat fs/open.c:1338 [inline]<br /> __arm64_sys_openat+0xb0/0xe0 fs/open.c:1338<br /> __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]<br /> invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]<br /> el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142<br /> do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206<br /> el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636<br /> el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654<br /> el0t_64_sync+0x18c/0x190<br /> Code: 97dafee4 340001b4 f9401328 2a1f03e0 (79402d14)<br /> ---[ end trace 0000000000000000 ]---<br /> <br /> Above issue may happens as follows:<br /> ntfs_new_inode<br /> mi_init<br /> mi-&gt;mrec = kmalloc(sbi-&gt;record_size, GFP_NOFS); --&gt;failed to allocate memory<br /> if (!mi-&gt;mrec)<br /> return -ENOMEM;<br /> iput<br /> iput_final<br /> evict<br /> ntfs_evict_inode<br /> ni_write_inode<br /> is_rec_inuse(ni-&gt;mi.mrec)-&gt; As &amp;#39;ni-&gt;mi.mrec&amp;#39; is NULL trigger NULL-ptr-deref<br /> <br /> To solve above issue if new inode failed make inode bad before call &amp;#39;iput()&amp;#39; in<br /> &amp;#39;ntfs_new_inode()&amp;#39;.