Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

fsdax: force clear dirty mark if CoW

XFS allows CoW on non-shared extents to combat fragmentation[1]. The old non-shared extent could be mwrited before, its dax entry is marked dirty.

This results in a WARNing:

[ 28.512349] ------------[ cut here ]------------ [ 28.512622] WARNING: CPU: 2 PID: 5255 at fs/dax.c:390 dax_insert_entry+0x342/0x390 [ 28.513050] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs lockd grace fscache netfs nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables [ 28.515462] CPU: 2 PID: 5255 Comm: fsstress Kdump: loaded Not tainted 6.3.0-rc1-00001-g85e1481e19c1-dirty #117 [ 28.515902] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Arch Linux 1.16.1-1-1 04/01/2014 [ 28.516307] RIP: 0010:dax_insert_entry+0x342/0x390 [ 28.516536] Code: 30 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 48 8b 45 20 48 83 c0 01 e9 e2 fe ff ff 48 8b 45 20 48 83 c0 01 e9 cd fe ff ff <0f> 0b e9 53 ff ff ff 48 8b 7c 24 08 31 f6 e8 1b 61 a1 00 eb 8c 48 [ 28.517417] RSP: 0000:ffffc9000845fb18 EFLAGS: 00010086 [ 28.517721] RAX: 0000000000000053 RBX: 0000000000000155 RCX: 000000000018824b [ 28.518113] RDX: 0000000000000000 RSI: ffffffff827525a6 RDI: 00000000ffffffff [ 28.518515] RBP: ffffea00062092c0 R08: 0000000000000000 R09: ffffc9000845f9c8 [ 28.518905] R1…