Bug 1220737 (CVE-2021-46989) - VUL-0: CVE-2021-46989: kernel: hfsplus: prevent corruption in shrinking truncate
Summary: VUL-0: CVE-2021-46989: kernel: hfsplus: prevent corruption in shrinking truncate
Status: RESOLVED FIXED
Alias: CVE-2021-46989
Product: SUSE Security Incidents
Classification: Novell Products
Component: Incidents (show other bugs)
Version: unspecified
Hardware: Other Other
: P3 - Medium : Normal
Target Milestone: ---
Assignee: Security Team bot
QA Contact: Security Team bot
URL: https://smash.suse.de/issue/395438/
Whiteboard: CVSSv3.1:SUSE:CVE-2021-46989:5.5:(AV:...
Keywords:
Depends on:
Blocks:
 
Reported: 2024-03-01 09:16 UTC by SMASH SMASH
Modified: 2024-05-16 03:43 UTC (History)
6 users (show)

See Also:
Found By: Security Response Team
Services Priority:
Business Priority:
Blocker: ---
Marketing QA Status: ---
IT Deployment: ---

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Description SMASH SMASH 2024-03-01 09:16:20 UTC 
In the Linux kernel, the following vulnerability has been resolved:

hfsplus: prevent corruption in shrinking truncate

I believe there are some issues introduced by commit 31651c607151
("hfsplus: avoid deadlock on file truncation")

HFS+ has extent records which always contains 8 extents.  In case the
first extent record in catalog file gets full, new ones are allocated from
extents overflow file.

In case shrinking truncate happens to middle of an extent record which
locates in extents overflow file, the logic in hfsplus_file_truncate() was
changed so that call to hfs_brec_remove() is not guarded any more.

Right action would be just freeing the extents that exceed the new size
inside extent record by calling hfsplus_free_extents(), and then check if
the whole extent record should be removed.  However since the guard
(blk_cnt > start) is now after the call to hfs_brec_remove(), this has
unfortunate effect that the last matching extent record is removed
unconditionally.

To reproduce this issue, create a file which has at least 10 extents, and
then perform shrinking truncate into middle of the last extent record, so
that the number of remaining extents is not under or divisible by 8.  This
causes the last extent record (8 extents) to be removed totally instead of
truncating into middle of it.  Thus this causes corruption, and lost data.

Fix for this is simply checking if the new truncated end is below the
start of this extent record, making it safe to remove the full extent
record.  However call to hfs_brec_remove() can't be moved to it's previous
place since we're dropping ->tree_lock and it can cause a race condition
and the cached info being invalidated possibly corrupting the node data.

Another issue is related to this one.  When entering into the block
(blk_cnt > start) we are not holding the ->tree_lock.  We break out from
the loop not holding the lock, but hfs_find_exit() does unlock it.  Not
sure if it's possible for someone else to take the lock under our feet,
but it can cause hard to debug errors and premature unlocking.  Even if
there's no real risk of it, the locking should still always be kept in
balance.  Thus taking the lock now just before the check.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-46989
https://www.cve.org/CVERecord?id=CVE-2021-46989
https://lore.kernel.org/linux-cve-announce/2024022825-CVE-2021-46989-8377@gregkh/T/#u

Patch:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c3187cf32216
Comment 1 Andrea Mattiazzo 2024-03-01 09:22:56 UTC 
Tracking as affected:
-cve/linux-5.3

cve/linux-5.14,stable and SLE15-SP6 already patched.
Comment 4 Anthony Iliopoulos 2024-03-01 15:01:57 UTC 
pushed to cve/linux-5.3 [1], pending kbuild testing/merging.

[1] https://kerncvs.suse.de/gitweb/?p=kernel-source.git;a=commit;h=cc37c7849d07da85a440b68f2fb94fb3890a9db5
Comment 5 Anthony Iliopoulos 2024-03-04 16:38:30 UTC 
reassigning back to security.
Comment 12 Maintenance Automation 2024-03-13 08:30:28 UTC 
SUSE-SU-2024:0857-1: An update that solves 67 vulnerabilities and has four security fixes can now be installed.

Category: security (important)
Bug References: 1200599, 1207653, 1212514, 1213456, 1216223, 1218195, 1218689, 1218915, 1219127, 1219128, 1219146, 1219295, 1219653, 1219827, 1219835, 1219915, 1220009, 1220140, 1220187, 1220238, 1220240, 1220241, 1220243, 1220250, 1220253, 1220255, 1220328, 1220330, 1220344, 1220398, 1220409, 1220416, 1220418, 1220421, 1220436, 1220444, 1220459, 1220469, 1220482, 1220526, 1220538, 1220570, 1220572, 1220599, 1220627, 1220641, 1220649, 1220660, 1220689, 1220700, 1220735, 1220736, 1220737, 1220742, 1220745, 1220767, 1220796, 1220825, 1220826, 1220831, 1220845, 1220860, 1220863, 1220870, 1220917, 1220918, 1220930, 1220931, 1220932, 1221039, 1221040
CVE References: CVE-2019-25162, CVE-2020-36777, CVE-2020-36784, CVE-2021-46904, CVE-2021-46905, CVE-2021-46906, CVE-2021-46915, CVE-2021-46924, CVE-2021-46929, CVE-2021-46932, CVE-2021-46934, CVE-2021-46953, CVE-2021-46964, CVE-2021-46966, CVE-2021-46968, CVE-2021-46974, CVE-2021-46989, CVE-2021-47005, CVE-2021-47012, CVE-2021-47013, CVE-2021-47054, CVE-2021-47060, CVE-2021-47061, CVE-2021-47069, CVE-2021-47076, CVE-2021-47078, CVE-2021-47083, CVE-2022-20154, CVE-2022-48627, CVE-2023-28746, CVE-2023-35827, CVE-2023-46343, CVE-2023-51042, CVE-2023-52340, CVE-2023-52429, CVE-2023-52439, CVE-2023-52443, CVE-2023-52445, CVE-2023-52448, CVE-2023-52449, CVE-2023-52451, CVE-2023-52463, CVE-2023-52475, CVE-2023-52478, CVE-2023-52482, CVE-2023-52502, CVE-2023-52530, CVE-2023-52531, CVE-2023-52532, CVE-2023-52569, CVE-2023-52574, CVE-2023-52597, CVE-2023-52605, CVE-2023-6817, CVE-2024-0340, CVE-2024-0607, CVE-2024-1151, CVE-2024-23849, CVE-2024-23851, CVE-2024-26585, CVE-2024-26586, CVE-2024-26589, CVE-2024-26593, CVE-2024-26595, CVE-2024-26602, CVE-2024-26607, CVE-2024-26622
Sources used:
openSUSE Leap 15.3 (src): kernel-obs-qa-5.3.18-150300.59.153.1, kernel-livepatch-SLE15-SP3_Update_42-1-150300.7.3.2, kernel-syms-5.3.18-150300.59.153.1, kernel-default-base-5.3.18-150300.59.153.2.150300.18.90.2, kernel-source-5.3.18-150300.59.153.2, kernel-obs-build-5.3.18-150300.59.153.2
SUSE Linux Enterprise Live Patching 15-SP3 (src): kernel-livepatch-SLE15-SP3_Update_42-1-150300.7.3.2
SUSE Linux Enterprise High Performance Computing LTSS 15 SP3 (src): kernel-default-base-5.3.18-150300.59.153.2.150300.18.90.2, kernel-source-5.3.18-150300.59.153.2, kernel-syms-5.3.18-150300.59.153.1, kernel-obs-build-5.3.18-150300.59.153.2
SUSE Linux Enterprise Server 15 SP3 LTSS 15-SP3 (src): kernel-default-base-5.3.18-150300.59.153.2.150300.18.90.2, kernel-source-5.3.18-150300.59.153.2, kernel-syms-5.3.18-150300.59.153.1, kernel-obs-build-5.3.18-150300.59.153.2
SUSE Linux Enterprise Server for SAP Applications 15 SP3 (src): kernel-default-base-5.3.18-150300.59.153.2.150300.18.90.2, kernel-source-5.3.18-150300.59.153.2, kernel-syms-5.3.18-150300.59.153.1, kernel-obs-build-5.3.18-150300.59.153.2
SUSE Enterprise Storage 7.1 (src): kernel-default-base-5.3.18-150300.59.153.2.150300.18.90.2, kernel-source-5.3.18-150300.59.153.2, kernel-syms-5.3.18-150300.59.153.1, kernel-obs-build-5.3.18-150300.59.153.2
SUSE Linux Enterprise Micro 5.1 (src): kernel-default-base-5.3.18-150300.59.153.2.150300.18.90.2
SUSE Linux Enterprise Micro 5.2 (src): kernel-default-base-5.3.18-150300.59.153.2.150300.18.90.2
SUSE Linux Enterprise Micro for Rancher 5.2 (src): kernel-default-base-5.3.18-150300.59.153.2.150300.18.90.2

NOTE: This line indicates an update has been released for the listed product(s). At times this might be only a partial fix. If you have questions please reach out to maintenance coordination.
Comment 13 Maintenance Automation 2024-03-13 08:30:45 UTC 
SUSE-SU-2024:0856-1: An update that solves 67 vulnerabilities and has seven security fixes can now be installed.

Category: security (important)
Bug References: 1155518, 1184436, 1185988, 1186286, 1200599, 1207653, 1212514, 1213456, 1216223, 1218195, 1218689, 1218915, 1219127, 1219128, 1219146, 1219295, 1219653, 1219827, 1219835, 1219915, 1220009, 1220140, 1220187, 1220238, 1220240, 1220241, 1220243, 1220250, 1220253, 1220255, 1220328, 1220330, 1220344, 1220398, 1220409, 1220416, 1220418, 1220421, 1220436, 1220444, 1220459, 1220469, 1220482, 1220526, 1220538, 1220570, 1220572, 1220599, 1220627, 1220641, 1220649, 1220660, 1220700, 1220735, 1220736, 1220737, 1220742, 1220745, 1220767, 1220796, 1220825, 1220826, 1220831, 1220845, 1220860, 1220863, 1220870, 1220917, 1220918, 1220930, 1220931, 1220932, 1221039, 1221040
CVE References: CVE-2019-25162, CVE-2020-36777, CVE-2020-36784, CVE-2021-46904, CVE-2021-46905, CVE-2021-46906, CVE-2021-46915, CVE-2021-46924, CVE-2021-46929, CVE-2021-46932, CVE-2021-46934, CVE-2021-46953, CVE-2021-46964, CVE-2021-46966, CVE-2021-46968, CVE-2021-46974, CVE-2021-46989, CVE-2021-47005, CVE-2021-47012, CVE-2021-47013, CVE-2021-47054, CVE-2021-47060, CVE-2021-47061, CVE-2021-47069, CVE-2021-47076, CVE-2021-47078, CVE-2021-47083, CVE-2022-20154, CVE-2022-48627, CVE-2023-28746, CVE-2023-35827, CVE-2023-46343, CVE-2023-51042, CVE-2023-52340, CVE-2023-52429, CVE-2023-52439, CVE-2023-52443, CVE-2023-52445, CVE-2023-52448, CVE-2023-52449, CVE-2023-52451, CVE-2023-52463, CVE-2023-52475, CVE-2023-52478, CVE-2023-52482, CVE-2023-52502, CVE-2023-52530, CVE-2023-52531, CVE-2023-52532, CVE-2023-52569, CVE-2023-52574, CVE-2023-52597, CVE-2023-52605, CVE-2023-6817, CVE-2024-0340, CVE-2024-0607, CVE-2024-1151, CVE-2024-23849, CVE-2024-23851, CVE-2024-26585, CVE-2024-26586, CVE-2024-26589, CVE-2024-26593, CVE-2024-26595, CVE-2024-26602, CVE-2024-26607, CVE-2024-26622
Sources used:
SUSE Linux Enterprise Micro 5.1 (src): kernel-source-rt-5.3.18-150300.161.1
SUSE Linux Enterprise Micro 5.2 (src): kernel-source-rt-5.3.18-150300.161.1
SUSE Linux Enterprise Micro for Rancher 5.2 (src): kernel-source-rt-5.3.18-150300.161.1

NOTE: This line indicates an update has been released for the listed product(s). At times this might be only a partial fix. If you have questions please reach out to maintenance coordination.
Comment 16 Maintenance Automation 2024-03-22 12:32:12 UTC 
SUSE-SU-2024:0926-1: An update that solves 65 vulnerabilities and has six security fixes can now be installed.

Category: security (important)
Bug References: 1155518, 1184436, 1185988, 1186286, 1200599, 1212514, 1213456, 1218689, 1218915, 1219127, 1219128, 1219146, 1219295, 1219653, 1219827, 1219835, 1220009, 1220140, 1220187, 1220238, 1220240, 1220241, 1220243, 1220250, 1220253, 1220255, 1220328, 1220330, 1220344, 1220398, 1220409, 1220416, 1220418, 1220421, 1220436, 1220444, 1220459, 1220469, 1220482, 1220526, 1220538, 1220570, 1220572, 1220599, 1220627, 1220641, 1220649, 1220660, 1220700, 1220735, 1220736, 1220737, 1220742, 1220745, 1220767, 1220796, 1220825, 1220826, 1220831, 1220845, 1220860, 1220863, 1220870, 1220917, 1220918, 1220930, 1220931, 1220932, 1221039, 1221040, 1221287
CVE References: CVE-2019-25162, CVE-2020-36777, CVE-2020-36784, CVE-2021-46904, CVE-2021-46905, CVE-2021-46906, CVE-2021-46915, CVE-2021-46924, CVE-2021-46929, CVE-2021-46932, CVE-2021-46934, CVE-2021-46953, CVE-2021-46964, CVE-2021-46966, CVE-2021-46974, CVE-2021-46989, CVE-2021-47005, CVE-2021-47012, CVE-2021-47013, CVE-2021-47054, CVE-2021-47060, CVE-2021-47061, CVE-2021-47069, CVE-2021-47076, CVE-2021-47078, CVE-2021-47083, CVE-2022-20154, CVE-2022-48627, CVE-2023-28746, CVE-2023-35827, CVE-2023-46343, CVE-2023-51042, CVE-2023-52340, CVE-2023-52429, CVE-2023-52439, CVE-2023-52443, CVE-2023-52445, CVE-2023-52448, CVE-2023-52449, CVE-2023-52451, CVE-2023-52463, CVE-2023-52475, CVE-2023-52478, CVE-2023-52482, CVE-2023-52502, CVE-2023-52530, CVE-2023-52531, CVE-2023-52532, CVE-2023-52569, CVE-2023-52574, CVE-2023-52597, CVE-2023-52605, CVE-2024-0340, CVE-2024-0607, CVE-2024-1151, CVE-2024-23849, CVE-2024-23851, CVE-2024-26585, CVE-2024-26586, CVE-2024-26589, CVE-2024-26593, CVE-2024-26595, CVE-2024-26602, CVE-2024-26607, CVE-2024-26622
Maintenance Incident: [SUSE:Maintenance:32904](https://smelt.suse.de/incident/32904/)
Sources used:
SUSE Linux Enterprise Live Patching 15-SP2 (src):
 kernel-livepatch-SLE15-SP2_Update_46-1-150200.5.3.2
SUSE Linux Enterprise High Performance Computing 15 SP2 LTSS 15-SP2 (src):
 kernel-obs-build-5.3.18-150200.24.183.1, kernel-syms-5.3.18-150200.24.183.1, kernel-source-5.3.18-150200.24.183.1, kernel-default-base-5.3.18-150200.24.183.1.150200.9.93.2
SUSE Linux Enterprise Server 15 SP2 LTSS 15-SP2 (src):
 kernel-obs-build-5.3.18-150200.24.183.1, kernel-syms-5.3.18-150200.24.183.1, kernel-source-5.3.18-150200.24.183.1, kernel-default-base-5.3.18-150200.24.183.1.150200.9.93.2
SUSE Linux Enterprise Server for SAP Applications 15 SP2 (src):
 kernel-obs-build-5.3.18-150200.24.183.1, kernel-syms-5.3.18-150200.24.183.1, kernel-source-5.3.18-150200.24.183.1, kernel-default-base-5.3.18-150200.24.183.1.150200.9.93.2

NOTE: This line indicates an update has been released for the listed product(s). At times this might be only a partial fix. If you have questions please reach out to maintenance coordination.