CVE-2022-49801: tracing: Fix memory leak in tracing_read_pipe()

Vulnerability summary

CVE-2022-49801 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.20% chance of exploitation in the next 30 days, higher than 9.2% of scored vulnerabilities.

Timeline

1. 01-05-2025
   PublishedVulnerability first disclosed.
2. 23-05-2026
   Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix memory leak in tracing_read_pipe() kmemleak reports this issue: unreferenced object 0xffff888105a18900 (size 128): comm "test_progs", pid 18933, jiffies 4336275356 (age 22801.766s) hex dump (first 32 bytes): 25 73 00 90 81 88 ff ff 26 05 00 00 42 01 58 04 %s......&...B.X. 03 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000560143a1>] __kmalloc_node_track_caller+0x4a/0x140 [<000000006af00822>] krealloc+0x8d/0xf0 [<00000000c309be6a>] trace_iter_expand_format+0x99/0x150 [<000000005a53bdb6>] trace_check_vprintf+0x1e0/0x11d0 [<0000000065629d9d>] trace_event_printf+0xb6/0xf0 [<000000009a690dc7>] trace_raw_output_bpf_trace_printk+0x89/0xc0 [<00000000d22db172>] print_trace_line+0x73c/0x1480 [<00000000cdba76ba>] tracing_read_pipe+0x45c/0x9f0 [<0000000015b58459>] vfs_read+0x17b/0x7c0 [<000000004aeee8ed>] ksys_read+0xed/0x1c0 [<0000000063d3d898>] do_syscall_64+0x3b/0x90 [<00000000a06dda7f>] entry_SYSCALL_64_after_hwframe+0x63/0xcd iter->fmt alloced in tracing_read_pipe() -> .. ->trace_iter_expand_format(), but not freed, to fix, add free in tracing_release_pipe()

• CWE-401Missing Release of Memory after Effective LifetimeThe product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.