{ "containers": { "cna": { "providerMetadata": { "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix race between transaction aborts and fsyncs leading to use-after-free\n\nThere is a race between a task aborting a transaction during a commit,\na task doing an fsync and the transaction kthread, which leads to an\nuse-after-free of the log root tree. When this happens, it results in a\nstack trace like the following:\n\n BTRFS info (device dm-0): forced readonly\n BTRFS warning (device dm-0): Skipping commit of aborted transaction.\n BTRFS: error (device dm-0) in cleanup_transaction:1958: errno=-5 IO failure\n BTRFS warning (device dm-0): lost page write due to IO error on /dev/mapper/error-test (-5)\n BTRFS warning (device dm-0): Skipping commit of aborted transaction.\n BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0xa4e8 len 4096 err no 10\n BTRFS error (device dm-0): error writing primary super block to device 1\n BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e000 len 4096 err no 10\n BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e008 len 4096 err no 10\n BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e010 len 4096 err no 10\n BTRFS: error (device dm-0) in write_all_supers:4110: errno=-5 IO failure (1 errors while writing supers)\n BTRFS: error (device dm-0) in btrfs_sync_log:3308: errno=-5 IO failure\n general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b68: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI\n CPU: 2 PID: 2458471 Comm: fsstress Not tainted 5.12.0-rc5-btrfs-next-84 #1\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014\n RIP: 0010:__mutex_lock+0x139/0xa40\n Code: c0 74 19 (...)\n RSP: 0018:ffff9f18830d7b00 EFLAGS: 00010202\n RAX: 6b6b6b6b6b6b6b68 RBX: 0000000000000001 RCX: 0000000000000002\n RDX: ffffffffb9c54d13 RSI: 0000000000000000 RDI: 0000000000000000\n RBP: ffff9f18830d7bc0 R08: 0000000000000000 R09: 0000000000000000\n R10: ffff9f18830d7be0 R11: 0000000000000001 R12: ffff8c6cd199c040\n R13: ffff8c6c95821358 R14: 00000000fffffffb R15: ffff8c6cbcf01358\n FS: 00007fa9140c2b80(0000) GS:ffff8c6fac600000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007fa913d52000 CR3: 000000013d2b4003 CR4: 0000000000370ee0\n DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n Call Trace:\n ? __btrfs_handle_fs_error+0xde/0x146 [btrfs]\n ? btrfs_sync_log+0x7c1/0xf20 [btrfs]\n ? btrfs_sync_log+0x7c1/0xf20 [btrfs]\n btrfs_sync_log+0x7c1/0xf20 [btrfs]\n btrfs_sync_file+0x40c/0x580 [btrfs]\n do_fsync+0x38/0x70\n __x64_sys_fsync+0x10/0x20\n do_syscall_64+0x33/0x80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n RIP: 0033:0x7fa9142a55c3\n Code: 8b 15 09 (...)\n RSP: 002b:00007fff26278d48 EFLAGS: 00000246 ORIG_RAX: 000000000000004a\n RAX: ffffffffffffffda RBX: 0000563c83cb4560 RCX: 00007fa9142a55c3\n RDX: 00007fff26278cb0 RSI: 00007fff26278cb0 RDI: 0000000000000005\n RBP: 0000000000000005 R08: 0000000000000001 R09: 00007fff26278d5c\n R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000340\n R13: 00007fff26278de0 R14: 00007fff26278d96 R15: 0000563c83ca57c0\n Modules linked in: btrfs dm_zero dm_snapshot dm_thin_pool (...)\n ---[ end trace ee2f1b19327d791d ]---\n\nThe steps that lead to this crash are the following:\n\n1) We are at transaction N;\n\n2) We have two tasks with a transaction handle attached to transaction N.\n Task A and Task B. Task B is doing an fsync;\n\n3) Task B is at btrfs_sync_log(), and has saved fs_info->log_root_tree\n into a local variable named 'log_root_tree' at the top of\n btrfs_sync_log(). Task B is about to call write_all_supers(), but\n before that...\n\n4) Task A calls btrfs_commit_transaction(), and after it sets the\n transaction state to TRANS_STATE_COMMIT_START, an error happens before\n it w\n---truncated---" } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/btrfs/transaction.c" ], "versions": [ { "version": "ef67963dac25", "lessThan": "a4794be7b00b", "status": "affected", "versionType": "git" }, { "version": "ef67963dac25", "lessThan": "633f7f216663", "status": "affected", "versionType": "git" }, { "version": "ef67963dac25", "lessThan": "e2da98788369", "status": "affected", "versionType": "git" }, { "version": "ef67963dac25", "lessThan": "061dde824535", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/btrfs/transaction.c" ], "versions": [ { "version": "5.7", "status": "affected" }, { "version": "0", "lessThan": "5.7", "status": "unaffected", "versionType": "custom" }, { "version": "5.10.36", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "custom" }, { "version": "5.11.20", "lessThanOrEqual": "5.11.*", "status": "unaffected", "versionType": "custom" }, { "version": "5.12.3", "lessThanOrEqual": "5.12.*", "status": "unaffected", "versionType": "custom" }, { "version": "5.13", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/a4794be7b00b7eda4b45fffd283ab7d76df7e5d6" }, { "url": "https://git.kernel.org/stable/c/633f7f216663587f17601eaa1cf2ac3d5654874c" }, { "url": "https://git.kernel.org/stable/c/e2da98788369bfba1138bada72765c47989a4338" }, { "url": "https://git.kernel.org/stable/c/061dde8245356d8864d29e25207aa4daa0be4d3c" } ], "title": "btrfs: fix race between transaction aborts and fsyncs leading to use-after-free", "x_generator": { "engine": "bippy-a5840b7849dd" } } }, "cveMetadata": { "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038", "cveID": "CVE-2021-46958", "requesterUserId": "gregkh@kernel.org", "serial": "1", "state": "PUBLISHED" }, "dataType": "CVE_RECORD", "dataVersion": "5.0" }