UBUNTU-CVE-2021-47219
In the Linux kernel, the following vulnerability has been resolved: scsi: scsi_debug: Fix out-of-bound read in resp_report_tgtpgs() The following issue was observed running syzkaller: BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:377 [inline] BUG: KASAN: slab-out-of-bounds in sg_copy_buffer+0x150/0x1c0 lib/scatterlist.c:831 Read of size 2132 at addr ffff8880aea95dc8 by task syz-executor.0/9815 CPU: 0 PID: 9815 Comm: syz-executor.0 Not tainted 4.19.202-00874-gfc0fe04215a9 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xe4/0x14a lib/dump_stack.c:118 print_address_description+0x73/0x280 mm/kasan/report.c:253 kasan_report_error mm/kasan/report.c:352 [inline] kasan_report+0x272/0x370 mm/kasan/report.c:410 memcpy+0x1f/0x50 mm/kasan/kasan.c:302 memcpy include/linux/string.h:377 [inline] sg_copy_buffer+0x150/0x1c0 lib/scatterlist.c:831 fill_from_dev_buffer+0x14f/0x340 drivers/scsi/scsi_debug.c:1021 resp_report_tgtpgs+0x5aa/0x770 drivers/scsi/scsi_debug.c:1772 schedule_resp+0x464/0x12f0 drivers/scsi/scsi_debug.c:4429 scsi_debug_queuecommand+0x467/0x1390 drivers/scsi/scsi_debug.c:5835 scsi_dispatch_cmd+0x3fc/0x9b0 drivers/scsi/scsi_lib.c:1896 scsi_request_fn+0x1042/0x1810 drivers/scsi/scsi_lib.c:2034 __blk_run_queue_uncond block/blk-core.c:464 [inline] __blk_run_queue+0x1a4/0x380 block/blk-core.c:484 blk_execute_rq_nowait+0x1c2/0x2d0 block/blk-exec.c:78 sg_common_write.isra.19+0xd74/0x1dc0 drivers/scsi/sg.c:847 sg_write.part.23+0x6e0/0xd00 drivers/scsi/sg.c:716 sg_write+0x64/0xa0 drivers/scsi/sg.c:622 __vfs_write+0xed/0x690 fs/read_write.c:485 kill_bdev:block_device:00000000e138492c vfs_write+0x184/0x4c0 fs/read_write.c:549 ksys_write+0x107/0x240 fs/read_write.c:599 do_syscall_64+0xc2/0x560 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe We get 'alen' from command its type is int. If userspace passes a large length we will get a negative 'alen'. Switch n, alen, and rlen to u32.
02 / AFFECTED SOFTWARE
Affected packages
50 explicit affected versions
6 explicit affected versions
12 explicit affected versions
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57 explicit affected versions
72 explicit affected versions
191 explicit affected versions
7 explicit affected versions
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71 explicit affected versions
35 explicit affected versions
18 explicit affected versions
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102 explicit affected versions
13 explicit affected versions
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23 explicit affected versions
107 explicit affected versions
1 explicit affected versions
1 explicit affected versions
21 explicit affected versions
16 explicit affected versions
10 explicit affected versions
57 explicit affected versions
7 explicit affected versions
12 explicit affected versions
12 explicit affected versions
1 explicit affected versions
7 explicit affected versions
89 explicit affected versions
12 explicit affected versions
105 explicit affected versions
113 explicit affected versions
12 explicit affected versions
100 explicit affected versions
106 explicit affected versions
10 explicit affected versions
174 explicit affected versions
37 explicit affected versions
10 explicit affected versions
1 explicit affected versions
37 explicit affected versions
26 explicit affected versions
13 explicit affected versions
1 explicit affected versions
29 explicit affected versions
93 explicit affected versions
13 explicit affected versions
1 explicit affected versions
87 explicit affected versions
105 explicit affected versions
33 explicit affected versions
23 explicit affected versions
10 explicit affected versions
100 explicit affected versions
11 explicit affected versions
12 explicit affected versions
123 explicit affected versions
7 explicit affected versions
12 explicit affected versions
103 explicit affected versions
2 explicit affected versions
116 explicit affected versions
151 explicit affected versions
137 explicit affected versions
10 explicit affected versions
26 explicit affected versions
38 explicit affected versions
13 explicit affected versions
123 explicit affected versions
63 explicit affected versions
16 explicit affected versions
3 explicit affected versions
77 explicit affected versions
1 explicit affected versions
70 explicit affected versions
51 explicit affected versions
76 explicit affected versions
12 explicit affected versions
27 explicit affected versions
1 explicit affected versions
1 explicit affected versions
81 explicit affected versions
8 explicit affected versions
5 explicit affected versions
8 explicit affected versions
1 explicit affected versions
10 explicit affected versions
92 explicit affected versions
13 explicit affected versions
56 explicit affected versions
7 explicit affected versions
78 explicit affected versions
10 explicit affected versions
12 explicit affected versions
91 explicit affected versions
44 explicit affected versions
16 explicit affected versions
3 explicit affected versions
13 explicit affected versions
26 explicit affected versions
37 explicit affected versions
38 explicit affected versions
9 explicit affected versions
11 explicit affected versions
7 explicit affected versions
84 explicit affected versions
64 explicit affected versions
127 explicit affected versions
106 explicit affected versions
4 explicit affected versions
99 explicit affected versions
43 explicit affected versions
58 explicit affected versions
130 explicit affected versions
151 explicit affected versions
10 explicit affected versions
8 explicit affected versions
14 explicit affected versions
92 explicit affected versions
4 explicit affected versions
78 explicit affected versions
1 explicit affected versions
53 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: scsi: scsi_debug: Fix out-of-bound read in resp_report_tgtpgs() The following issue was observed running syzkaller: BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:377 [inline] BUG: KASAN: slab-out-of-bounds in sg_copy_buffer+0x150/0x1c0 lib/scatterlist.c:831 Read of size 2132 at addr ffff8880aea95dc8 by task syz-executor.0/9815 CPU: 0 PID: 9815 Comm: syz-executor.0 Not tainted 4.19.202-00874-gfc0fe04215a9 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xe4/0x14a lib/dump_stack.c:118 print_address_description+0x73/0x280 mm/kasan/report.c:253 kasan_report_error mm/kasan/report.c:352 [inline] kasan_report+0x272/0x370 mm/kasan/report.c:410 memcpy+0x1f/0x50 mm/kasan/kasan.c:302 memcpy include/linux/string.h:377 [inline] sg_copy_buffer+0x150/0x1c0 lib/scatterlist.c:831 fill_from_dev_buffer+0x14f/0x340 drivers/scsi/scsi_debug.c:1021 resp_report_tgtpgs+0x5aa/0x770 drivers/scsi/scsi_debug.c:1772 schedule_resp+0x464/0x12f0 drivers/scsi/scsi_debug.c:4429 scsi_debug_queuecommand+0x467/0x1390 drivers/scsi/scsi_debug.c:5835 scsi_dispatch_cmd+0x3fc/0x9b0 drivers/scsi/scsi_lib.c:1896 scsi_request_fn+0x1042/0x1810 drivers/scsi/scsi_lib.c:2034 __blk_run_queue_uncond block/blk-core.c:464 [inline] __blk_run_queue+0x1a4/0x380 block/blk-core.c:484 blk_execute_rq_nowait+0x1c2/0x2d0 block/blk-exec.c:78 sg_common_write.isra.19+0xd74/0x1dc0 drivers/scsi/sg.c:847 sg_write.part.23+0x6e0/0xd00 drivers/scsi/sg.c:716 sg_write+0x64/0xa0 drivers/scsi/sg.c:622 __vfs_write+0xed/0x690 fs/read_write.c:485 kill_bdev:block_device:00000000e138492c vfs_write+0x184/0x4c0 fs/read_write.c:549 ksys_write+0x107/0x240 fs/read_write.c:599 do_syscall_64+0xc2/0x560 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe We get 'alen' from command its type is int. If userspace passes a large length we will get a negative 'alen'. Switch n, alen, and rlen to u32.
05 / REFERENCES
Further evidence
- https://git.kernel.org/linus/f347c26836c270199de1599c3cd466bb7747caa9
- https://git.kernel.org/stable/c/66523553fa62c7878fc5441dc4e82be71934eb77
- https://git.kernel.org/stable/c/8440377e1a5644779b4c8d013aa2a917f5fc83c3
- https://git.kernel.org/stable/c/f347c26836c270199de1599c3cd466bb7747caa9
- https://ubuntu.com/security/CVE-2021-47219
- https://ubuntu.com/security/notices/USN-7391-1
- https://ubuntu.com/security/notices/USN-7392-1
- https://ubuntu.com/security/notices/USN-7392-2
- https://ubuntu.com/security/notices/USN-7392-3
- https://ubuntu.com/security/notices/USN-7392-4
- https://ubuntu.com/security/notices/USN-7393-1
- https://ubuntu.com/security/notices/USN-7401-1
- https://ubuntu.com/security/notices/USN-7413-1
- https://ubuntu.com/security/notices/USN-7463-1
- https://ubuntu.com/security/notices/USN-7496-1
- https://ubuntu.com/security/notices/USN-7496-3
- https://ubuntu.com/security/notices/USN-7496-4
- https://ubuntu.com/security/notices/USN-7496-5
- https://ubuntu.com/security/notices/USN-7506-1
- https://ubuntu.com/security/notices/USN-7506-2
- https://ubuntu.com/security/notices/USN-7506-3
- https://ubuntu.com/security/notices/USN-7506-4
- https://ubuntu.com/security/notices/USN-7539-1
- https://ubuntu.com/security/notices/USN-7540-1
- https://www.cve.org/CVERecord?id=CVE-2021-47219