linux-stable/arch/riscv/include/asm/kexec.h
Li Huafei 96df59b1ae
RISC-V: kexec: Fix memory leak of fdt buffer
This is reported by kmemleak detector:

unreferenced object 0xff60000082864000 (size 9588):
  comm "kexec", pid 146, jiffies 4294900634 (age 64.788s)
  hex dump (first 32 bytes):
    d0 0d fe ed 00 00 12 ed 00 00 00 48 00 00 11 40  ...........H...@
    00 00 00 28 00 00 00 11 00 00 00 02 00 00 00 00  ...(............
  backtrace:
    [<00000000f95b17c4>] kmemleak_alloc+0x34/0x3e
    [<00000000b9ec8e3e>] kmalloc_order+0x9c/0xc4
    [<00000000a95cf02e>] kmalloc_order_trace+0x34/0xb6
    [<00000000f01e68b4>] __kmalloc+0x5c2/0x62a
    [<000000002bd497b2>] kvmalloc_node+0x66/0xd6
    [<00000000906542fa>] of_kexec_alloc_and_setup_fdt+0xa6/0x6ea
    [<00000000e1166bde>] elf_kexec_load+0x206/0x4ec
    [<0000000036548e09>] kexec_image_load_default+0x40/0x4c
    [<0000000079fbe1b4>] sys_kexec_file_load+0x1c4/0x322
    [<0000000040c62c03>] ret_from_syscall+0x0/0x2

In elf_kexec_load(), a buffer is allocated via kvmalloc() to store fdt.
While it's not freed back to system when kexec kernel is reloaded or
unloaded.  Then memory leak is caused.  Fix it by introducing riscv
specific function arch_kimage_file_post_load_cleanup(), and freeing the
buffer there.

Fixes: 6261586e0c ("RISC-V: Add kexec_file support")
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Liao Chang <liaochang1@huawei.com>
Link: https://lore.kernel.org/r/20221104095658.141222-1-lihuafei1@huawei.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-12-05 10:59:51 -08:00

72 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2019 FORTH-ICS/CARV
* Nick Kossifidis <mick@ics.forth.gr>
*/
#ifndef _RISCV_KEXEC_H
#define _RISCV_KEXEC_H
#include <asm/page.h> /* For PAGE_SIZE */
/* Maximum physical address we can use pages from */
#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
/* Maximum address we can reach in physical address mode */
#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
/* Maximum address we can use for the control code buffer */
#define KEXEC_CONTROL_MEMORY_LIMIT (-1UL)
/* Reserve a page for the control code buffer */
#define KEXEC_CONTROL_PAGE_SIZE PAGE_SIZE
#define KEXEC_ARCH KEXEC_ARCH_RISCV
extern void riscv_crash_save_regs(struct pt_regs *newregs);
static inline void
crash_setup_regs(struct pt_regs *newregs,
struct pt_regs *oldregs)
{
if (oldregs)
memcpy(newregs, oldregs, sizeof(struct pt_regs));
else
riscv_crash_save_regs(newregs);
}
#define ARCH_HAS_KIMAGE_ARCH
struct kimage_arch {
void *fdt; /* For CONFIG_KEXEC_FILE */
unsigned long fdt_addr;
};
extern const unsigned char riscv_kexec_relocate[];
extern const unsigned int riscv_kexec_relocate_size;
typedef void (*riscv_kexec_method)(unsigned long first_ind_entry,
unsigned long jump_addr,
unsigned long fdt_addr,
unsigned long hartid,
unsigned long va_pa_off);
extern riscv_kexec_method riscv_kexec_norelocate;
#ifdef CONFIG_KEXEC_FILE
extern const struct kexec_file_ops elf_kexec_ops;
struct purgatory_info;
int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
Elf_Shdr *section,
const Elf_Shdr *relsec,
const Elf_Shdr *symtab);
#define arch_kexec_apply_relocations_add arch_kexec_apply_relocations_add
struct kimage;
int arch_kimage_file_post_load_cleanup(struct kimage *image);
#define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_cleanup
#endif
#endif