tracing: Fix reading strings from synthetic events
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 5.15.75, 5.19.17, 6.0.3
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
In the Linux kernel, the following vulnerability has been resolved: tracing: Fix reading strings from synthetic events The follow commands caused a crash: cd /sys/kernel/tracing echo 's:open char file[]' > dynamic_events echo 'hist:keys=common_pid:file=filename:onchange($file).trace(open,$file)' > events/syscalls/sys_enter_openat/trigger' echo 1 > events/synthetic/open/enable BOOM! The problem is that the synthetic event field "char file[]" will read the value given to it as a string without any memory checks to make sure the address is valid. The above example will pass in the user space address and the sythetic event code will happily call strlen() on it and then strscpy() where either one will cause an oops when accessing user space addresses. Use the helper functions from trace_kprobe and trace_eprobe that can read strings safely (and actually succeed when the address is from user space and the memory is mapped in). Now the above can show: packagekitd-1721 [000] ...2. 104.597170: open: file=/usr/lib/rpm/fileattrs/cmake.attr in:imjournal-978 [006] ...2. 104.599642: open: file=/var/lib/rsyslog/imjournal.state.tmp packagekitd-1721 [000] ...2. 104.626308: open: file=/usr/lib/rpm/fileattrs/debuginfo.attr
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From bd82631d7ccdc894af2738e47abcba2cb6e7dea9 · fixed in d9c79fbcbdb6cb10c07c85040eaf615180b26c48; From bd82631d7ccdc894af2738e47abcba2cb6e7dea9 · fixed in 149198d0b884e4606ed1d29b330c70016d878276; From bd82631d7ccdc894af2738e47abcba2cb6e7dea9 · fixed in f8bae1853196b52ede50950387f5b48cf83b9815; From bd82631d7ccdc894af2738e47abcba2cb6e7dea9 · fixed in 0934ae9977c27133449b6dd8c6213970e7eece38
- Linux Linux
5.10
- KernelLinux
From 5.10.0 · fixed in 5.15.75; From 5.16.0 · fixed in 5.19.17; From 5.20.0 · fixed in 6.0.3