UBUNTU-CVE-2024-38605
In the Linux kernel, the following vulnerability has been resolved: ALSA: core: Fix NULL module pointer assignment at card init The commit 81033c6b584b ("ALSA: core: Warn on empty module") introduced a WARN_ON() for a NULL module pointer passed at snd_card object creation, and it also wraps the code around it with '#ifdef MODULE'. This works in most cases, but the devils are always in details. "MODULE" is defined when the target code (i.e. the sound core) is built as a module; but this doesn't mean that the caller is also built-in or not. Namely, when only the sound core is built-in (CONFIG_SND=y) while the driver is a module (CONFIG_SND_USB_AUDIO=m), the passed module pointer is ignored even if it's non-NULL, and card->module remains as NULL. This would result in the missing module reference up/down at the device open/close, leading to a race with the code execution after the module removal. For addressing the bug, move the assignment of card->module again out of ifdef. The WARN_ON() is still wrapped with ifdef because the module can be really NULL when all sound drivers are built-in. Note that we keep 'ifdef MODULE' for WARN_ON(), otherwise it would lead to a false-positive NULL module check. Admittedly it won't catch perfectly, i.e. no check is performed when CONFIG_SND=y. But, it's no real problem as it's only for debugging, and the condition is pretty rare.
02 / AFFECTED SOFTWARE
Affected packages
11 explicit affected versions
35 explicit affected versions
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6 explicit affected versions
12 explicit affected versions
19 explicit affected versions
6 explicit affected versions
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8 explicit affected versions
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44 explicit affected versions
10 explicit affected versions
1 explicit affected versions
7 explicit affected versions
51 explicit affected versions
7 explicit affected versions
50 explicit affected versions
2 explicit affected versions
13 explicit affected versions
4 explicit affected versions
35 explicit affected versions
11 explicit affected versions
16 explicit affected versions
18 explicit affected versions
12 explicit affected versions
37 explicit affected versions
7 explicit affected versions
13 explicit affected versions
4 explicit affected versions
23 explicit affected versions
11 explicit affected versions
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16 explicit affected versions
10 explicit affected versions
9 explicit affected versions
7 explicit affected versions
12 explicit affected versions
42 explicit affected versions
12 explicit affected versions
14 explicit affected versions
7 explicit affected versions
12 explicit affected versions
12 explicit affected versions
2 explicit affected versions
11 explicit affected versions
3 explicit affected versions
37 explicit affected versions
13 explicit affected versions
1 explicit affected versions
10 explicit affected versions
31 explicit affected versions
26 explicit affected versions
13 explicit affected versions
6 explicit affected versions
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13 explicit affected versions
55 explicit affected versions
1 explicit affected versions
2 explicit affected versions
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15 explicit affected versions
33 explicit affected versions
23 explicit affected versions
10 explicit affected versions
1 explicit affected versions
11 explicit affected versions
12 explicit affected versions
7 explicit affected versions
12 explicit affected versions
42 explicit affected versions
36 explicit affected versions
52 explicit affected versions
10 explicit affected versions
26 explicit affected versions
9 explicit affected versions
1 explicit affected versions
2 explicit affected versions
10 explicit affected versions
13 explicit affected versions
9 explicit affected versions
16 explicit affected versions
55 explicit affected versions
10 explicit affected versions
43 explicit affected versions
3 explicit affected versions
2 explicit affected versions
51 explicit affected versions
7 explicit affected versions
12 explicit affected versions
41 explicit affected versions
27 explicit affected versions
27 explicit affected versions
3 explicit affected versions
8 explicit affected versions
16 explicit affected versions
5 explicit affected versions
8 explicit affected versions
10 explicit affected versions
6 explicit affected versions
13 explicit affected versions
13 explicit affected versions
7 explicit affected versions
46 explicit affected versions
10 explicit affected versions
13 explicit affected versions
12 explicit affected versions
44 explicit affected versions
16 explicit affected versions
3 explicit affected versions
13 explicit affected versions
26 explicit affected versions
41 explicit affected versions
37 explicit affected versions
10 explicit affected versions
14 explicit affected versions
38 explicit affected versions
44 explicit affected versions
9 explicit affected versions
44 explicit affected versions
11 explicit affected versions
2 explicit affected versions
52 explicit affected versions
7 explicit affected versions
25 explicit affected versions
4 explicit affected versions
1 explicit affected versions
1 explicit affected versions
50 explicit affected versions
13 explicit affected versions
43 explicit affected versions
10 explicit affected versions
8 explicit affected versions
5 explicit affected versions
14 explicit affected versions
4 explicit affected versions
11 explicit affected versions
1 explicit affected versions
3 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: ALSA: core: Fix NULL module pointer assignment at card init The commit 81033c6b584b ("ALSA: core: Warn on empty module") introduced a WARN_ON() for a NULL module pointer passed at snd_card object creation, and it also wraps the code around it with '#ifdef MODULE'. This works in most cases, but the devils are always in details. "MODULE" is defined when the target code (i.e. the sound core) is built as a module; but this doesn't mean that the caller is also built-in or not. Namely, when only the sound core is built-in (CONFIG_SND=y) while the driver is a module (CONFIG_SND_USB_AUDIO=m), the passed module pointer is ignored even if it's non-NULL, and card->module remains as NULL. This would result in the missing module reference up/down at the device open/close, leading to a race with the code execution after the module removal. For addressing the bug, move the assignment of card->module again out of ifdef. The WARN_ON() is still wrapped with ifdef because the module can be really NULL when all sound drivers are built-in. Note that we keep 'ifdef MODULE' for WARN_ON(), otherwise it would lead to a false-positive NULL module check. Admittedly it won't catch perfectly, i.e. no check is performed when CONFIG_SND=y. But, it's no real problem as it's only for debugging, and the condition is pretty rare.
05 / REFERENCES
Further evidence
- https://git.kernel.org/linus/39381fe7394e5eafac76e7e9367e7351138a29c1
- https://git.kernel.org/stable/c/39381fe7394e5eafac76e7e9367e7351138a29c1
- https://git.kernel.org/stable/c/6b8374ee2cabcf034faa34e69a855dc496a9ec12
- https://git.kernel.org/stable/c/c935e72139e6d523defd60fe875c01eb1f9ea5c5
- https://git.kernel.org/stable/c/d7ff29a429b56f04783152ad7bbd7233b740e434
- https://git.kernel.org/stable/c/e007476725730c1a68387b54b7629486d8a8301e
- https://git.kernel.org/stable/c/e644036a3e2b2c9b3eee3c61b5d31c2ca8b5ba92
- https://git.kernel.org/stable/c/e7e0ca200772bdb2fdc6d43d32d341e87a36f811
- https://ubuntu.com/security/CVE-2024-38605
- https://ubuntu.com/security/notices/USN-6949-1
- https://ubuntu.com/security/notices/USN-6949-2
- https://ubuntu.com/security/notices/USN-6952-1
- https://ubuntu.com/security/notices/USN-6952-2
- https://ubuntu.com/security/notices/USN-6955-1
- https://ubuntu.com/security/notices/USN-7007-1
- https://ubuntu.com/security/notices/USN-7007-2
- https://ubuntu.com/security/notices/USN-7007-3
- https://ubuntu.com/security/notices/USN-7009-1
- https://ubuntu.com/security/notices/USN-7009-2
- https://ubuntu.com/security/notices/USN-7019-1
- https://www.cve.org/CVERecord?id=CVE-2024-38605