From cbc32023ddbdf4baa3d9dc513a2184a84080a5a2 Mon Sep 17 00:00:00 2001 From: Li Huafei Date: Fri, 4 Nov 2022 17:56:58 +0800 Subject: RISC-V: kexec: Fix memory leak of elf header buffer This is reported by kmemleak detector: unreferenced object 0xff2000000403d000 (size 4096): comm "kexec", pid 146, jiffies 4294900633 (age 64.792s) hex dump (first 32 bytes): 7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00 .ELF............ 04 00 f3 00 01 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000566ca97c>] kmemleak_vmalloc+0x3c/0xbe [<00000000979283d8>] __vmalloc_node_range+0x3ac/0x560 [<00000000b4b3712a>] __vmalloc_node+0x56/0x62 [<00000000854f75e2>] vzalloc+0x2c/0x34 [<00000000e9a00db9>] crash_prepare_elf64_headers+0x80/0x30c [<0000000067e8bf48>] elf_kexec_load+0x3e8/0x4ec [<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 vzalloc() to store elf headers. While it's not freed back to system when kdump kernel is reloaded or unloaded, or when image->elf_header is successfully set and then fails to load kdump kernel for some reason. Fix it by freeing the buffer in arch_kimage_file_post_load_cleanup(). Fixes: 8acea455fafa ("RISC-V: Support for kexec_file on panic") Signed-off-by: Li Huafei Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20221104095658.141222-2-lihuafei1@huawei.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/elf_kexec.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/riscv') diff --git a/arch/riscv/kernel/elf_kexec.c b/arch/riscv/kernel/elf_kexec.c index ff30fcb43f47..5372b708fae2 100644 --- a/arch/riscv/kernel/elf_kexec.c +++ b/arch/riscv/kernel/elf_kexec.c @@ -26,6 +26,10 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image) kvfree(image->arch.fdt); image->arch.fdt = NULL; + vfree(image->elf_headers); + image->elf_headers = NULL; + image->elf_headers_sz = 0; + return kexec_image_post_load_cleanup_default(image); } -- cgit v1.2.3