CVE-2022-50323: In the Linux kernel, the following vulnerability has been resolved: net: do not sense pfmemalloc status in skb_append_pagefrags() skb_append_pagefrags() is…

PriorityP421medium5.5CVSS 3.1

AVLACLPRLUINSUCNINAH

EPSS

0.14%

4.1th percentile

In the Linux kernel, the following vulnerability has been resolved: net: do not sense pfmemalloc status in skb_append_pagefrags() skb_append_pagefrags() is used by af_unix and udp sendpage() implementation so far. In commit 326140063946 ("tcp: TX zerocopy should not sense pfmemalloc status") we explained why we should not sense pfmemalloc status for pages owned by user space. We should also use skb_fill_page_desc_noacc() in skb_append_pagefrags() to avoid following KCSAN report: BUG: KCSAN: data-race in lru_add_fn / skb_append_pagefrags write to 0xffffea00058fc1c8 of 8 bytes by task 17319 on cpu 0: __list_add include/linux/list.h:73 [inline] list_add include/linux/list.h:88 [inline] lruvec_add_folio include/linux/mm_inline.h:323 [inline] lru_add_fn+0x327/0x410 mm/swap.c:228 folio_batch_move_lru+0x1e1/0x2a0 mm/swap.c:246 lru_add_drain_cpu+0x73/0x250 mm/swap.c:669 lru_add_drain+0x21/0x60 mm/swap.c:773 free_pages_and_swap_cache+0x16/0x70 mm/swap_state.c:311 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline] tlb_flush_mmu_free mm/mmu_gather.c:256 [inline] tlb_flush_mmu+0x5b2/0x640 mm/mmu_gather.c:263 tlb_finish_mmu+0x86/0x100 mm/mmu_gather.c:363 exit_mmap+0x190/0x4d0 mm/mmap.c:3098 __mmput+0x27/0x1b0 kernel/fork.c:1185 mmput+0x3d/0x50 kernel/fork.c:1207 copy_process+0x19fc/0x2100 kernel/fork.c:2518 kernel_clone+0x166/0x550 kernel/fork.c:2671 __do_sys_clone kernel/fork.c:2812 [inline] __se_sys_clone kernel/fork.c:2796 [inline] __x64_sys_clone+0xc3/0xf0 kernel/fork.c:2796 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffffea00058fc1c8 of 8 bytes by task 17325 on cpu 1: page_is_pfmemalloc include/linux/mm.h:1817 [inline] __skb_fill_page_desc include/linux/skbuff.h:2432 [inline] skb_fill_page_desc include/linux/skbuff.h:2453 [inline] skb_append_pagefrags+0x210/0x600 net/core/skbuff.c:3974 unix_stream_sendpage+0x45e/0x990 net/unix/af_unix.c:2338 kernel_sendpage+0x1

Affected

16 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 6.0.7-1 (bookworm)	linux 6.0.7-1 (bookworm)
linux	linux	—	—
linux	linux	—	—
linux	linux	>= 3261400639463a853ba2b3be8bd009c2a8089775 < 847a2859814b31392340a2b16604b25afaa92dcc	847a2859814b31392340a2b16604b25afaa92dcc
linux	linux	>= 3261400639463a853ba2b3be8bd009c2a8089775 < 228ebc41dfab5b5d34cd76835ddb0ca8ee12f513	228ebc41dfab5b5d34cd76835ddb0ca8ee12f513
linux	linux	>= 5.15.68 < 5.15.77	5.15.77
linux	linux	>= 5.19.9 < 5.20	5.20
linux	linux	>= 8527c9a6bf8e54fef0a8d3d7d8874a48c725c915 < 92b4c5c3fa810212da20088bcc6c0a77fc8607bd	92b4c5c3fa810212da20088bcc6c0a77fc8607bd
linux	linux_kernel	—	—
linux	linux_kernel	—	—
linux	linux_kernel	>= 0 < 6.0.7-1	6.0.7-1
linux	linux_kernel	>= 0 < 6.0.7-1	6.0.7-1
linux	linux_kernel	>= 0 < 6.0.7-1	6.0.7-1
linux	linux_kernel	>= 5.15.68 < 5.15.77	5.15.77
linux	linux_kernel	>= 5.19.9 < 6.0	6.0
linux	linux_kernel	>= 6.0.1 < 6.0.7	6.0.7

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

osv5.5MEDIUM

vendor_debian5.5MEDIUM

vendor_redhat5.5MEDIUM

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