CVE-2023-54171

In the Linux kernel, the following vulnerability has been resolved:

tracing: Fix memory leak of iter->temp when reading trace_pipe

kmemleak reports: unreferenced object 0xffff88814d14e200 (size 256): comm cat, pid 336, jiffies 4294871818 (age 779.490s) hex dump (first 32 bytes): 04 00 01 03 00 00 00 00 08 00 00 00 00 00 00 00 ……………. 0c d8 c8 9b ff ff ff ff 04 5a ca 9b ff ff ff ff ………Z…… backtrace: [] __kmalloc+0x4f/0x140 [] trace_find_next_entry+0xbb/0x1d0 [] trace_print_lat_context+0xaf/0x4e0 [] print_trace_line+0x3e0/0x950 [] tracing_read_pipe+0x2d9/0x5a0 [] vfs_read+0x143/0x520 [] ksys_read+0xbd/0x160 [] do_syscall_64+0x3f/0x90 [] entry_SYSCALL_64_after_hwframe+0x6e/0xd8

when reading file trace_pipe, iter->temp is allocated or relocated in trace_find_next_entry() but not freed before trace_pipe is closed.

To fix it, free iter->temp in tracing_release_pipe().

Affected Software

References

• https://git.kernel.org/stable/c/1a1e793e021d75cd0accd8f329ec9456e5cd105e
• https://git.kernel.org/stable/c/3f42d57a76e7e96585f08855554e002218cbca0c
• https://git.kernel.org/stable/c/954792db9f61b6c0b8a94b8831fed5f146014029
• https://git.kernel.org/stable/c/be970e22c53d5572b2795b79da9716ada937023b
• https://git.kernel.org/stable/c/d5a821896360cc8b93a15bd888fabc858c038dc0