CVE-2021-47649

published 2025-02-26

CVE-2021-47649: In the Linux kernel, the following vulnerability has been resolved: udmabuf: validate ubuf->pagecount Syzbot has reported GPF in…

Priority P4 19 medium 5.5 CVSS 3.1

AV L AC L PR L UI N S U C N I N A H

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

udmabuf: validate ubuf->pagecount

Syzbot has reported GPF in sg_alloc_append_table_from_pages(). The
problem was in ubuf->pages == ZERO_PTR.

ubuf->pagecount is calculated from arguments passed from user-space. If
user creates udmabuf with list.size == 0 then ubuf->pagecount will be
also equal to zero; it causes kmalloc_array() to return ZERO_PTR.

Fix it by validating ubuf->pagecount before passing it to
kmalloc_array().

Affected

17 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 5.17.3-1 (bookworm)	linux 5.17.3-1 (bookworm)
linux	linux	—	—
linux	linux	>= fbb0de795078190a9834b3409e4b009cfb18a6d4 < 5d50f851dd307c07ca5591297093f19967c834a9	5d50f851dd307c07ca5591297093f19967c834a9
linux	linux	>= fbb0de795078190a9834b3409e4b009cfb18a6d4 < b267a8118c2b171bf7d67b90ed64154eeab9fae0	b267a8118c2b171bf7d67b90ed64154eeab9fae0
linux	linux	>= fbb0de795078190a9834b3409e4b009cfb18a6d4 < 811b667cefbea9cb7511a874b169d6a92907137e	811b667cefbea9cb7511a874b169d6a92907137e
linux	linux	>= fbb0de795078190a9834b3409e4b009cfb18a6d4 < a3728d32fc61eb0fe283cb8ff60b2c8f751e2202	a3728d32fc61eb0fe283cb8ff60b2c8f751e2202
linux	linux	>= fbb0de795078190a9834b3409e4b009cfb18a6d4 < 9e9b4a269f84d3230f2af84ff42322db676440d9	9e9b4a269f84d3230f2af84ff42322db676440d9
linux	linux	>= fbb0de795078190a9834b3409e4b009cfb18a6d4 < 2b6dd600dd72573c23ea180b5b0b2f1813405882	2b6dd600dd72573c23ea180b5b0b2f1813405882
linux	linux_kernel	>= 0 < 5.10.113-1	5.10.113-1
linux	linux_kernel	>= 0 < 5.17.3-1	5.17.3-1
linux	linux_kernel	>= 0 < 5.17.3-1	5.17.3-1
linux	linux_kernel	>= 0 < 5.17.3-1	5.17.3-1
linux	linux_kernel	>= 4.20 < 5.4.189	5.4.189
linux	linux_kernel	>= 5.11 < 5.15.33	5.15.33
linux	linux_kernel	>= 5.16 < 5.16.19	5.16.19
linux	linux_kernel	>= 5.17 < 5.17.2	5.17.2
linux	linux_kernel	>= 5.5 < 5.10.110	5.10.110

CVSS provenance

nvd v3.1 5.5 MEDIUM CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

osv 5.5 MEDIUM

vendor_debian 5.5 MEDIUM

vendor_redhat 5.5 MEDIUM

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