Description
In the Linux kernel, the following vulnerability has been resolved: NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback Add PF_KCOMPACTD flag and current_is_kcompactd() helper to check for it so nfs_release_folio() can skip calling nfs_wb_folio() from kcompactd. Otherwise NFS can deadlock waiting for kcompactd enduced writeback which recurses back to NFS (which triggers writeback to NFSD via NFS loopback mount on the same host, NFSD blocks waiting for XFS's call to __filemap_get_folio): 6070.550357] INFO: task kcompactd0:58 blocked for more than 4435 seconds. {--- [58] "kcompactd0" [<0>] folio_wait_bit+0xe8/0x200 [<0>] folio_wait_writeback+0x2b/0x80 [<0>] nfs_wb_folio+0x80/0x1b0 [nfs] [<0>] nfs_release_folio+0x68/0x130 [nfs] [<0>] split_huge_page_to_list_to_order+0x362/0x840 [<0>] migrate_pages_batch+0x43d/0xb90 [<0>] migrate_pages_sync+0x9a/0x240 [<0>] migrate_pages+0x93c/0x9f0 [<0>] compact_zone+0x8e2/0x1030 [<0>] compact_node+0xdb/0x120 [<0>] kcompactd+0x121/0x2e0 [<0>] kthread+0xcf/0x100 [<0>] ret_from_fork+0x31/0x40 [<0>] ret_from_fork_asm+0x1a/0x30 ---} [akpm@linux-foundation.org: fix build]
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
96780ca55e3cbf4f150fd5a833a61492c9947b5b to < ab0727d6e2196682351c25c1dd112136f6991f11affected96780ca55e3cbf4f150fd5a833a61492c9947b5b to < 5ae31c54cff745832b9bd5b32e71f3d1b607cd1eaffected96780ca55e3cbf4f150fd5a833a61492c9947b5b to < 8253ff29edcb429a9a6c75710941c6a16a9a34b1affected96780ca55e3cbf4f150fd5a833a61492c9947b5b to < ce6d9c1c2b5cc785016faa11b48b6cd317eb367eaffected
Linux Linux
Default version status: affected
6.3affected0 to < 6.3unaffected6.6.83 to ≤ 6.6.*unaffected6.12.19 to ≤ 6.12.*unaffected6.13.7 to ≤ 6.13.*unaffected6.14 to ≤ *unaffected