Bug 1222532 (CVE-2024-26726)

Summary:	VUL-0: CVE-2024-26726: kernel: btrfs: don't drop extent_map for free space inode on write error
Product:	[Novell Products] SUSE Security Incidents	Reporter:	SMASH SMASH <smash_bz>
Component:	Incidents	Assignee:	Security Team bot <security-team>
Status:	IN_PROGRESS ---	QA Contact:	Security Team bot <security-team>
Severity:	Normal
Priority:	P3 - Medium	CC:	abergmann, mhocko
Version:	unspecified
Target Milestone:	---
Hardware:	Other
OS:	Other
URL:	https://smash.suse.de/issue/400142/
Whiteboard:	CVSSv3.1:SUSE:CVE-2024-26726:5.5:(AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Found By:	Security Response Team	Services Priority:
Business Priority:		Blocker:	---
Marketing QA Status:	---	IT Deployment:	---

Description SMASH SMASH 2024-04-09 10:26:26 UTC

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

btrfs: don't drop extent_map for free space inode on write error

While running the CI for an unrelated change I hit the following panic
with generic/648 on btrfs_holes_spacecache.

assertion failed: block_start != EXTENT_MAP_HOLE, in fs/btrfs/extent_io.c:1385
------------[ cut here ]------------
kernel BUG at fs/btrfs/extent_io.c:1385!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 2695096 Comm: fsstress Kdump: loaded Tainted: G        W          6.8.0-rc2+ #1
RIP: 0010:__extent_writepage_io.constprop.0+0x4c1/0x5c0
Call Trace:
 <TASK>
 extent_write_cache_pages+0x2ac/0x8f0
 extent_writepages+0x87/0x110
 do_writepages+0xd5/0x1f0
 filemap_fdatawrite_wbc+0x63/0x90
 __filemap_fdatawrite_range+0x5c/0x80
 btrfs_fdatawrite_range+0x1f/0x50
 btrfs_write_out_cache+0x507/0x560
 btrfs_write_dirty_block_groups+0x32a/0x420
 commit_cowonly_roots+0x21b/0x290
 btrfs_commit_transaction+0x813/0x1360
 btrfs_sync_file+0x51a/0x640
 __x64_sys_fdatasync+0x52/0x90
 do_syscall_64+0x9c/0x190
 entry_SYSCALL_64_after_hwframe+0x6e/0x76

This happens because we fail to write out the free space cache in one
instance, come back around and attempt to write it again.  However on
the second pass through we go to call btrfs_get_extent() on the inode to
get the extent mapping.  Because this is a new block group, and with the
free space inode we always search the commit root to avoid deadlocking
with the tree, we find nothing and return a EXTENT_MAP_HOLE for the
requested range.

This happens because the first time we try to write the space cache out
we hit an error, and on an error we drop the extent mapping.  This is
normal for normal files, but the free space cache inode is special.  We
always expect the extent map to be correct.  Thus the second time
through we end up with a bogus extent map.

Since we're deprecating this feature, the most straightforward way to
fix this is to simply skip dropping the extent map range for this failed
range.

I shortened the test by using error injection to stress the area to make
it easier to reproduce.  With this patch in place we no longer panic
with my error injection test.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-26726
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2024/CVE-2024-26726.mbox
https://git.kernel.org/stable/c/02f2b95b00bf57d20320ee168b30fb7f3db8e555
https://git.kernel.org/stable/c/7bddf18f474f166c19f91b2baf67bf7c5eda03f7
https://git.kernel.org/stable/c/a4b7741c8302e28073bfc6dd1c2e73598e5e535e
https://git.kernel.org/stable/c/5571e41ec6e56e35f34ae9f5b3a335ef510e0ade
https://www.cve.org/CVERecord?id=CVE-2024-26726
https://bugzilla.redhat.com/show_bug.cgi?id=2273128

Comment 1 Alexander Bergmann 2024-04-09 10:26:49 UTC

Only affecting ALP.

Comment 16 Maintenance Automation 2024-06-21 12:31:02 UTC

SUSE-SU-2024:2135-1: An update that solves 428 vulnerabilities, contains 15 features and has 78 security fixes can now be installed.

Category: security (important)
Bug References: 1012628, 1065729, 1181674, 1187716, 1193599, 1194869, 1207948, 1208593, 1209657, 1213573, 1214852, 1215199, 1216196, 1216358, 1216702, 1217169, 1217384, 1217408, 1217489, 1217750, 1217959, 1218205, 1218336, 1218447, 1218562, 1218779, 1218917, 1219104, 1219170, 1219596, 1219623, 1219834, 1220021, 1220045, 1220120, 1220148, 1220328, 1220342, 1220428, 1220430, 1220569, 1220587, 1220738, 1220783, 1220915, 1221044, 1221276, 1221293, 1221303, 1221375, 1221504, 1221612, 1221615, 1221635, 1221645, 1221649, 1221765, 1221777, 1221783, 1221816, 1221829, 1221830, 1221858, 1222115, 1222173, 1222264, 1222273, 1222294, 1222301, 1222303, 1222304, 1222307, 1222357, 1222366, 1222368, 1222371, 1222378, 1222379, 1222385, 1222422, 1222426, 1222428, 1222437, 1222445, 1222459, 1222464, 1222489, 1222522, 1222525, 1222527, 1222531, 1222532, 1222549, 1222550, 1222557, 1222559, 1222563, 1222585, 1222586, 1222596, 1222606, 1222608, 1222613, 1222615, 1222618, 1222622, 1222624, 1222627, 1222630, 1222635, 1222721, 1222727, 1222769, 1222771, 1222772, 1222775, 1222777, 1222780, 1222782, 1222793, 1222799, 1222801, 1222968, 1223007, 1223011, 1223015, 1223016, 1223020, 1223023, 1223024, 1223030, 1223033, 1223034, 1223035, 1223038, 1223039, 1223041, 1223045, 1223046, 1223051, 1223052, 1223058, 1223060, 1223061, 1223076, 1223077, 1223084, 1223111, 1223113, 1223138, 1223143, 1223187, 1223189, 1223190, 1223191, 1223198, 1223202, 1223285, 1223315, 1223338, 1223369, 1223380, 1223384, 1223390, 1223439, 1223462, 1223532, 1223539, 1223575, 1223590, 1223591, 1223592, 1223593, 1223625, 1223628, 1223629, 1223633, 1223634, 1223637, 1223641, 1223643, 1223649, 1223650, 1223651, 1223652, 1223653, 1223654, 1223655, 1223660, 1223661, 1223663, 1223664, 1223665, 1223666, 1223668, 1223669, 1223670, 1223671, 1223675, 1223677, 1223678, 1223686, 1223692, 1223693, 1223695, 1223696, 1223698, 1223705, 1223712, 1223718, 1223728, 1223732, 1223735, 1223739, 1223741, 1223744, 1223745, 1223747, 1223748, 1223749, 1223750, 1223752, 1223754, 1223757, 1223759, 1223761, 1223762, 1223774, 1223782, 1223787, 1223788, 1223789, 1223790, 1223802, 1223805, 1223810, 1223822, 1223827, 1223831, 1223834, 1223838, 1223869, 1223870, 1223871, 1223872, 1223874, 1223944, 1223945, 1223946, 1223991, 1224076, 1224096, 1224098, 1224099, 1224137, 1224166, 1224174, 1224177, 1224180, 1224181, 1224331, 1224348, 1224423, 1224429, 1224430, 1224432, 1224433, 1224437, 1224438, 1224442, 1224443, 1224445, 1224449, 1224477, 1224479, 1224480, 1224481, 1224482, 1224486, 1224487, 1224488, 1224491, 1224492, 1224493, 1224494, 1224495, 1224500, 1224501, 1224502, 1224504, 1224505, 1224506, 1224507, 1224508, 1224509, 1224511, 1224513, 1224517, 1224519, 1224521, 1224524, 1224525, 1224526, 1224530, 1224531, 1224534, 1224537, 1224541, 1224542, 1224543, 1224546, 1224550, 1224552, 1224553, 1224555, 1224557, 1224558, 1224559, 1224562, 1224565, 1224566, 1224567, 1224568, 1224569, 1224571, 1224573, 1224576, 1224577, 1224578, 1224579, 1224580, 1224581, 1224582, 1224585, 1224586, 1224587, 1224588, 1224592, 1224596, 1224598, 1224600, 1224601, 1224602, 1224603, 1224605, 1224607, 1224608, 1224609, 1224611, 1224613, 1224615, 1224617, 1224618, 1224620, 1224621, 1224622, 1224623, 1224624, 1224626, 1224627, 1224628, 1224629, 1224630, 1224632, 1224633, 1224634, 1224636, 1224637, 1224638, 1224639, 1224640, 1224643, 1224644, 1224645, 1224646, 1224647, 1224648, 1224649, 1224650, 1224651, 1224652, 1224653, 1224654, 1224657, 1224660, 1224663, 1224664, 1224665, 1224666, 1224667, 1224668, 1224671, 1224672, 1224674, 1224675, 1224676, 1224677, 1224678, 1224679, 1224680, 1224681, 1224682, 1224683, 1224685, 1224686, 1224687, 1224688, 1224692, 1224696, 1224697, 1224699, 1224701, 1224703, 1224704, 1224705, 1224706, 1224707, 1224709, 1224710, 1224712, 1224714, 1224716, 1224717, 1224718, 1224719, 1224720, 1224721, 1224722, 1224723, 1224725, 1224727, 1224728, 1224729, 1224730, 1224731, 1224732, 1224733, 1224736, 1224738, 1224739, 1224740, 1224741, 1224742, 1224747, 1224749, 1224763, 1224764, 1224765, 1224766, 1224790, 1224792, 1224793, 1224803, 1224804, 1224866, 1224936, 1224989, 1225007, 1225053, 1225133, 1225134, 1225136, 1225172, 1225502, 1225578, 1225579, 1225580, 1225593, 1225605, 1225607, 1225610, 1225616, 1225618, 1225640, 1225642, 1225692, 1225694, 1225695, 1225696, 1225698, 1225699, 1225704, 1225705, 1225708, 1225710, 1225712, 1225714, 1225715, 1225720, 1225722, 1225728, 1225734, 1225735, 1225736, 1225747, 1225748, 1225749, 1225750, 1225756, 1225765, 1225766, 1225769, 1225773, 1225775, 1225842, 1225945
CVE References: CVE-2023-0160, CVE-2023-47233, CVE-2023-52434, CVE-2023-52458, CVE-2023-52463, CVE-2023-52472, CVE-2023-52483, CVE-2023-52492, CVE-2023-52503, CVE-2023-52591, CVE-2023-52608, CVE-2023-52616, CVE-2023-52618, CVE-2023-52631, CVE-2023-52635, CVE-2023-52640, CVE-2023-52641, CVE-2023-52645, CVE-2023-52652, CVE-2023-52653, CVE-2023-52654, CVE-2023-52655, CVE-2023-52657, CVE-2023-52658, CVE-2023-52659, CVE-2023-52660, CVE-2023-52661, CVE-2023-52662, CVE-2023-52663, CVE-2023-52664, CVE-2023-52667, CVE-2023-52669, CVE-2023-52670, CVE-2023-52671, CVE-2023-52673, CVE-2023-52674, CVE-2023-52675, CVE-2023-52676, CVE-2023-52678, CVE-2023-52679, CVE-2023-52680, CVE-2023-52681, CVE-2023-52683, CVE-2023-52685, CVE-2023-52686, CVE-2023-52687, CVE-2023-52690, CVE-2023-52691, CVE-2023-52692, CVE-2023-52693, CVE-2023-52694, CVE-2023-52695, CVE-2023-52696, CVE-2023-52697, CVE-2023-52698, CVE-2023-52771, CVE-2023-52772, CVE-2023-52860, CVE-2023-52882, CVE-2023-6238, CVE-2023-6270, CVE-2023-6531, CVE-2023-7042, CVE-2024-0639, CVE-2024-21823, CVE-2024-22099, CVE-2024-23848, CVE-2024-24861, CVE-2024-25739, CVE-2024-26601, CVE-2024-26611, CVE-2024-26614, CVE-2024-26632, CVE-2024-26638, CVE-2024-26642, CVE-2024-26643, CVE-2024-26652, CVE-2024-26654, CVE-2024-26656, CVE-2024-26657, CVE-2024-26671, CVE-2024-26673, CVE-2024-26674, CVE-2024-26675, CVE-2024-26679, CVE-2024-26684, CVE-2024-26685, CVE-2024-26692, CVE-2024-26696, CVE-2024-26697, CVE-2024-26704, CVE-2024-26714, CVE-2024-26726, CVE-2024-26731, CVE-2024-26733, CVE-2024-26736, CVE-2024-26737, CVE-2024-26739, CVE-2024-26740, CVE-2024-26742, CVE-2024-26756, CVE-2024-26757, CVE-2024-26760, CVE-2024-267600, CVE-2024-26761, CVE-2024-26764, CVE-2024-26769, CVE-2024-26772, CVE-2024-26773, CVE-2024-26774, CVE-2024-26775, CVE-2024-26779, CVE-2024-26783, CVE-2024-26786, CVE-2024-26791, CVE-2024-26793, CVE-2024-26794, CVE-2024-26802, CVE-2024-26805, CVE-2024-26807, CVE-2024-26815, CVE-2024-26816, CVE-2024-26822, CVE-2024-26828, CVE-2024-26832, CVE-2024-26836, CVE-2024-26844, CVE-2024-26846, CVE-2024-26848, CVE-2024-26853, CVE-2024-26854, CVE-2024-26855, CVE-2024-26856, CVE-2024-26857, CVE-2024-26858, CVE-2024-26860, CVE-2024-26861, CVE-2024-26862, CVE-2024-26866, CVE-2024-26868, CVE-2024-26870, CVE-2024-26878, CVE-2024-26881, CVE-2024-26882, CVE-2024-26883, CVE-2024-26884, CVE-2024-26885, CVE-2024-26898, CVE-2024-26899, CVE-2024-26900, CVE-2024-26901, CVE-2024-26903, CVE-2024-26906, CVE-2024-26909, CVE-2024-26921, CVE-2024-26922, CVE-2024-26923, CVE-2024-26925, CVE-2024-26928, CVE-2024-26932, CVE-2024-26933, CVE-2024-26934, CVE-2024-26935, CVE-2024-26937, CVE-2024-26938, CVE-2024-26940, CVE-2024-26943, CVE-2024-26945, CVE-2024-26946, CVE-2024-26948, CVE-2024-26949, CVE-2024-26950, CVE-2024-26951, CVE-2024-26956, CVE-2024-26957, CVE-2024-26958, CVE-2024-26960, CVE-2024-26961, CVE-2024-26962, CVE-2024-26963, CVE-2024-26964, CVE-2024-26972, CVE-2024-26973, CVE-2024-26978, CVE-2024-26979, CVE-2024-26981, CVE-2024-26982, CVE-2024-26983, CVE-2024-26984, CVE-2024-26986, CVE-2024-26988, CVE-2024-26989, CVE-2024-26990, CVE-2024-26991, CVE-2024-26992, CVE-2024-26993, CVE-2024-26994, CVE-2024-26995, CVE-2024-26996, CVE-2024-26997, CVE-2024-26999, CVE-2024-27000, CVE-2024-27001, CVE-2024-27002, CVE-2024-27003, CVE-2024-27004, CVE-2024-27008, CVE-2024-27013, CVE-2024-27014, CVE-2024-27022, CVE-2024-27027, CVE-2024-27028, CVE-2024-27029, CVE-2024-27030, CVE-2024-27031, CVE-2024-27036, CVE-2024-27046, CVE-2024-27056, CVE-2024-27057, CVE-2024-27062, CVE-2024-27067, CVE-2024-27080, CVE-2024-27388, CVE-2024-27389, CVE-2024-27393, CVE-2024-27395, CVE-2024-27396, CVE-2024-27398, CVE-2024-27399, CVE-2024-27400, CVE-2024-27401, CVE-2024-27405, CVE-2024-27408, CVE-2024-27410, CVE-2024-27411, CVE-2024-27412, CVE-2024-27413, CVE-2024-27416, CVE-2024-27417, CVE-2024-27418, CVE-2024-27431, CVE-2024-27432, CVE-2024-27434, CVE-2024-27435, CVE-2024-27436, CVE-2024-35784, CVE-2024-35786, CVE-2024-35788, CVE-2024-35789, CVE-2024-35790, CVE-2024-35791, CVE-2024-35794, CVE-2024-35795, CVE-2024-35796, CVE-2024-35799, CVE-2024-35800, CVE-2024-35801, CVE-2024-35803, CVE-2024-35804, CVE-2024-35806, CVE-2024-35808, CVE-2024-35809, CVE-2024-35810, CVE-2024-35811, CVE-2024-35812, CVE-2024-35813, CVE-2024-35814, CVE-2024-35815, CVE-2024-35817, CVE-2024-35819, CVE-2024-35821, CVE-2024-35822, CVE-2024-35823, CVE-2024-35824, CVE-2024-35825, CVE-2024-35828, CVE-2024-35829, CVE-2024-35830, CVE-2024-35833, CVE-2024-35834, CVE-2024-35835, CVE-2024-35836, CVE-2024-35837, CVE-2024-35838, CVE-2024-35841, CVE-2024-35842, CVE-2024-35845, CVE-2024-35847, CVE-2024-35849, CVE-2024-35850, CVE-2024-35851, CVE-2024-35852, CVE-2024-35854, CVE-2024-35860, CVE-2024-35861, CVE-2024-35862, CVE-2024-35863, CVE-2024-35864, CVE-2024-35865, CVE-2024-35866, CVE-2024-35867, CVE-2024-35868, CVE-2024-35869, CVE-2024-35870, CVE-2024-35872, CVE-2024-35875, CVE-2024-35877, CVE-2024-35878, CVE-2024-35879, CVE-2024-35883, CVE-2024-35885, CVE-2024-35887, CVE-2024-35889, CVE-2024-35891, CVE-2024-35895, CVE-2024-35901, CVE-2024-35903, CVE-2024-35904, CVE-2024-35905, CVE-2024-35907, CVE-2024-35909, CVE-2024-35911, CVE-2024-35912, CVE-2024-35914, CVE-2024-35915, CVE-2024-35916, CVE-2024-35917, CVE-2024-35921, CVE-2024-35922, CVE-2024-35924, CVE-2024-35927, CVE-2024-35928, CVE-2024-35930, CVE-2024-35931, CVE-2024-35932, CVE-2024-35933, CVE-2024-35935, CVE-2024-35936, CVE-2024-35937, CVE-2024-35938, CVE-2024-35940, CVE-2024-35943, CVE-2024-35944, CVE-2024-35945, CVE-2024-35946, CVE-2024-35947, CVE-2024-35950, CVE-2024-35951, CVE-2024-35952, CVE-2024-35953, CVE-2024-35954, CVE-2024-35955, CVE-2024-35956, CVE-2024-35958, CVE-2024-35959, CVE-2024-35960, CVE-2024-35961, CVE-2024-35963, CVE-2024-35964, CVE-2024-35965, CVE-2024-35966, CVE-2024-35967, CVE-2024-35969, CVE-2024-35971, CVE-2024-35972, CVE-2024-35973, CVE-2024-35974, CVE-2024-35975, CVE-2024-35977, CVE-2024-35978, CVE-2024-35981, CVE-2024-35982, CVE-2024-35984, CVE-2024-35986, CVE-2024-35989, CVE-2024-35990, CVE-2024-35991, CVE-2024-35992, CVE-2024-35995, CVE-2024-35997, CVE-2024-35999, CVE-2024-36002, CVE-2024-36006, CVE-2024-36007, CVE-2024-36009, CVE-2024-36011, CVE-2024-36012, CVE-2024-36013, CVE-2024-36014, CVE-2024-36015, CVE-2024-36016, CVE-2024-36018, CVE-2024-36019, CVE-2024-36020, CVE-2024-36021, CVE-2024-36025, CVE-2024-36026, CVE-2024-36029, CVE-2024-36030, CVE-2024-36032, CVE-2024-36880, CVE-2024-36885, CVE-2024-36890, CVE-2024-36891, CVE-2024-36893, CVE-2024-36894, CVE-2024-36895, CVE-2024-36896, CVE-2024-36897, CVE-2024-36898, CVE-2024-36906, CVE-2024-36918, CVE-2024-36921, CVE-2024-36922, CVE-2024-36928, CVE-2024-36930, CVE-2024-36931, CVE-2024-36936, CVE-2024-36940, CVE-2024-36941, CVE-2024-36942, CVE-2024-36944, CVE-2024-36947, CVE-2024-36949, CVE-2024-36950, CVE-2024-36951, CVE-2024-36955, CVE-2024-36959
Jira References: PED-3184, PED-3311, PED-3535, PED-4486, PED-4593, PED-5062, PED-542, PED-5728, PED-5853, PED-6079, PED-6252, PED-7542, PED-7619, PED-8111, PED-8240
Maintenance Incident: [SUSE:Maintenance:34127](https://smelt.suse.de/incident/34127/)
Sources used:
openSUSE Leap 15.6 (src):
 kernel-syms-azure-6.4.0-150600.8.5.1, kernel-source-azure-6.4.0-150600.8.5.4
Public Cloud Module 15-SP6 (src):
 kernel-syms-azure-6.4.0-150600.8.5.1, kernel-source-azure-6.4.0-150600.8.5.4

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.