| Message ID | 20210204174951.25771-2-nramas@linux.microsoft.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2,1/2] ima: Free IMA measurement buffer on error | expand |
On Thu, Feb 04, 2021 at 09:49:51AM -0800, Lakshmi Ramasubramanian wrote: > IMA allocates kernel virtual memory to carry forward the measurement > list, from the current kernel to the next kernel on kexec system call, > in ima_add_kexec_buffer() function. This buffer is not freed before > completing the kexec system call resulting in memory leak. > > Add ima_buffer field in "struct kimage" to store the virtual address > of the buffer allocated for the IMA measurement list. > Free the memory allocated for the IMA measurement list in > kimage_file_post_load_cleanup() function. > > Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> > Suggested-by: Tyler Hicks <tyhicks@linux.microsoft.com> > Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> > Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com> > Fixes: 7b8589cc29e7 ("ima: on soft reboot, save the measurement list") > --- > include/linux/kexec.h | 5 +++++ > kernel/kexec_file.c | 5 +++++ > security/integrity/ima/ima_kexec.c | 2 ++ > 3 files changed, 12 insertions(+) <formletter> This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html for how to do this properly. </formletter>
diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 9e93bef52968..5f61389f5f36 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -300,6 +300,11 @@ struct kimage { /* Information for loading purgatory */ struct purgatory_info purgatory_info; #endif + +#ifdef CONFIG_IMA_KEXEC + /* Virtual address of IMA measurement buffer for kexec syscall */ + void *ima_buffer; +#endif }; /* kexec interface functions */ diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index b02086d70492..5c3447cf7ad5 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -166,6 +166,11 @@ void kimage_file_post_load_cleanup(struct kimage *image) vfree(pi->sechdrs); pi->sechdrs = NULL; +#ifdef CONFIG_IMA_KEXEC + vfree(image->ima_buffer); + image->ima_buffer = NULL; +#endif /* CONFIG_IMA_KEXEC */ + /* See if architecture has anything to cleanup post load */ arch_kimage_file_post_load_cleanup(image); diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c index 206ddcaa5c67..e29bea3dd4cc 100644 --- a/security/integrity/ima/ima_kexec.c +++ b/security/integrity/ima/ima_kexec.c @@ -129,6 +129,8 @@ void ima_add_kexec_buffer(struct kimage *image) return; } + image->ima_buffer = kexec_buffer; + pr_debug("kexec measurement buffer for the loaded kernel at 0x%lx.\n", kbuf.mem); }