5.15-stable review patch. If anyone has any objections, please let me know.
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From: Baoquan He bhe@redhat.com
commit 8d9ffb2fe65a6c4ef114e8d4f947958a12751bbe upstream.
The kdump kernel is broken on SME systems with CONFIG_IMA_KEXEC=y enabled. Debugging traced the issue back to
b69a2afd5afc ("x86/kexec: Carry forward IMA measurement log on kexec").
Testing was previously not conducted on SME systems with CONFIG_IMA_KEXEC enabled, which led to the oversight, with the following incarnation:
... ima: No TPM chip found, activating TPM-bypass! Loading compiled-in module X.509 certificates Loaded X.509 cert 'Build time autogenerated kernel key: 18ae0bc7e79b64700122bb1d6a904b070fef2656' ima: Allocated hash algorithm: sha256 Oops: general protection fault, probably for non-canonical address 0xcfacfdfe6660003e: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.11.0-rc2+ #14 Hardware name: Dell Inc. PowerEdge R7425/02MJ3T, BIOS 1.20.0 05/03/2023 RIP: 0010:ima_restore_measurement_list Call Trace: <TASK> ? show_trace_log_lvl ? show_trace_log_lvl ? ima_load_kexec_buffer ? __die_body.cold ? die_addr ? exc_general_protection ? asm_exc_general_protection ? ima_restore_measurement_list ? vprintk_emit ? ima_load_kexec_buffer ima_load_kexec_buffer ima_init ? __pfx_init_ima init_ima ? __pfx_init_ima do_one_initcall do_initcalls ? __pfx_kernel_init kernel_init_freeable kernel_init ret_from_fork ? __pfx_kernel_init ret_from_fork_asm </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- ... Kernel panic - not syncing: Fatal exception Kernel Offset: disabled Rebooting in 10 seconds..
Adding debug printks showed that the stored addr and size of ima_kexec buffer are not decrypted correctly like:
ima: ima_load_kexec_buffer, buffer:0xcfacfdfe6660003e, size:0xe48066052d5df359
Three types of setup_data info
— SETUP_EFI, - SETUP_IMA, and - SETUP_RNG_SEED
are passed to the kexec/kdump kernel. Only the ima_kexec buffer experienced incorrect decryption. Debugging identified a bug in early_memremap_is_setup_data(), where an incorrect range calculation occurred due to the len variable in struct setup_data ended up only representing the length of the data field, excluding the struct's size, and thus leading to miscalculation.
Address a similar issue in memremap_is_setup_data() while at it.
[ bp: Heavily massage. ]
Fixes: b3c72fc9a78e ("x86/boot: Introduce setup_indirect") Signed-off-by: Baoquan He bhe@redhat.com Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Acked-by: Tom Lendacky thomas.lendacky@amd.com Cc: stable@kernel.org Link: https://lore.kernel.org/r/20240911081615.262202-3-bhe@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/mm/ioremap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -641,7 +641,8 @@ static bool memremap_is_setup_data(resou paddr_next = data->next; len = data->len;
- if ((phys_addr > paddr) && (phys_addr < (paddr + len))) { + if ((phys_addr > paddr) && + (phys_addr < (paddr + sizeof(struct setup_data) + len))) { memunmap(data); return true; } @@ -703,7 +704,8 @@ static bool __init early_memremap_is_set paddr_next = data->next; len = data->len;
- if ((phys_addr > paddr) && (phys_addr < (paddr + len))) { + if ((phys_addr > paddr) && + (phys_addr < (paddr + sizeof(struct setup_data) + len))) { early_memunmap(data, sizeof(*data)); return true; }