CVE-2023-53247: In the Linux kernel, the following vulnerability has been resolved: btrfs: set_page_extent_mapped after read_folio in btrfs_cont_expand While trying to get the…

PriorityP420medium5.5CVSS 3.1

AVLACLPRLUINSUCNINAH

EPSS

0.13%

3.3th percentile

In the Linux kernel, the following vulnerability has been resolved: btrfs: set_page_extent_mapped after read_folio in btrfs_cont_expand While trying to get the subpage blocksize tests running, I hit the following panic on generic/476 assertion failed: PagePrivate(page) && page->private, in fs/btrfs/subpage.c:229 kernel BUG at fs/btrfs/subpage.c:229! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 1 PID: 1453 Comm: fsstress Not tainted 6.4.0-rc7+ #12 Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20230301gitf80f052277c8-26.fc38 03/01/2023 pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) pc : btrfs_subpage_assert+0xbc/0xf0 lr : btrfs_subpage_assert+0xbc/0xf0 Call trace: btrfs_subpage_assert+0xbc/0xf0 btrfs_subpage_clear_checked+0x38/0xc0 btrfs_page_clear_checked+0x48/0x98 btrfs_truncate_block+0x5d0/0x6a8 btrfs_cont_expand+0x5c/0x528 btrfs_write_check.isra.0+0xf8/0x150 btrfs_buffered_write+0xb4/0x760 btrfs_do_write_iter+0x2f8/0x4b0 btrfs_file_write_iter+0x1c/0x30 do_iter_readv_writev+0xc8/0x158 do_iter_write+0x9c/0x210 vfs_iter_write+0x24/0x40 iter_file_splice_write+0x224/0x390 direct_splice_actor+0x38/0x68 splice_direct_to_actor+0x12c/0x260 do_splice_direct+0x90/0xe8 generic_copy_file_range+0x50/0x90 vfs_copy_file_range+0x29c/0x470 __arm64_sys_copy_file_range+0xcc/0x498 invoke_syscall.constprop.0+0x80/0xd8 do_el0_svc+0x6c/0x168 el0_svc+0x50/0x1b0 el0t_64_sync_handler+0x114/0x120 el0t_64_sync+0x194/0x198 This happens because during btrfs_cont_expand we'll get a page, set it as mapped, and if it's not Uptodate we'll read it. However between the read and re-locking the page we could have called release_folio() on the page, but left the page in the file mapping. release_folio() can clear the page private, and thus further down we blow up when we go to modify the subpage bits. Fix this by putting the set_page_extent_mapped() after the read. This is safe because read_folio() will call set_page_extent_mapped() before it does the read, and t

Affected

14 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 6.1.52-1 (bookworm)	linux 6.1.52-1 (bookworm)
linux	linux	—	—
linux	linux	>= 32443de3382be98c0a8b8f6f50d23da2e10c4117 < 0a5e0bc8e8618e32a6ca64450867628eb0a627bf	0a5e0bc8e8618e32a6ca64450867628eb0a627bf
linux	linux	>= 32443de3382be98c0a8b8f6f50d23da2e10c4117 < a5880e69cf7fe4a0bb1eabae02205352d1b59b7b	a5880e69cf7fe4a0bb1eabae02205352d1b59b7b
linux	linux	>= 32443de3382be98c0a8b8f6f50d23da2e10c4117 < 17b17fcd6d446b95904a6929c40012ee7f0afc0c	17b17fcd6d446b95904a6929c40012ee7f0afc0c
linux	linux_kernel	< 6.1.42	6.1.42
linux	linux_kernel	—	—
linux	linux_kernel	>= 0 < 6.1.52-1	6.1.52-1
linux	linux_kernel	>= 0 < 6.4.11-1	6.4.11-1
linux	linux_kernel	>= 0 < 6.4.11-1	6.4.11-1
linux	linux_kernel	>= 6.2 < 6.4.7	6.4.7
msrc	cbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0	—	—
msrc	cbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0	—	—
msrc	cbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0	—	—

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_msrc5.5MEDIUM

vendor_redhat5.5MEDIUM

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