summaryrefslogtreecommitdiff
path: root/arch/powerpc/kernel/process.c
diff options
context:
space:
mode:
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-10-07 07:05:43 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-10-07 07:05:43 +0200
commitcd2093cb45a4d9332d4e5a2170602f74bca298a4 (patch)
treeecf65f1ae67000b94f5a4890af9b140d566df216 /arch/powerpc/kernel/process.c
parentc1d84a1b42ef70d8ae601df9cadedc7ed4f1beb1 (diff)
parentac1788cc7da4ce54edcfd2e499afdb0a23d5c41d (diff)
Merge tag 'powerpc-4.19-4' of https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Michael writes: "powerpc fixes for 4.19 #4 Four regression fixes. A fix for a change to lib/xz which broke our zImage loader when building with XZ compression. OK'ed by Herbert who merged the original patch. The recent fix we did to avoid patching __init text broke some 32-bit machines, fix that. Our show_user_instructions() could be tricked into printing kernel memory, add a check to avoid that. And a fix for a change to our NUMA initialisation logic, which causes crashes in some kdump configurations. Thanks to: Christophe Leroy, Hari Bathini, Jann Horn, Joel Stanley, Meelis Roos, Murilo Opsfelder Araujo, Srikar Dronamraju." * tag 'powerpc-4.19-4' of https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/numa: Skip onlining a offline node in kdump path powerpc: Don't print kernel instructions in show_user_instructions() powerpc/lib: fix book3s/32 boot failure due to code patching lib/xz: Put CRC32_POLY_LE in xz_private.h
Diffstat (limited to 'arch/powerpc/kernel/process.c')
-rw-r--r--arch/powerpc/kernel/process.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 913c5725cdb2a..bb6ac471a784e 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1306,6 +1306,16 @@ void show_user_instructions(struct pt_regs *regs)
pc = regs->nip - (instructions_to_print * 3 / 4 * sizeof(int));
+ /*
+ * Make sure the NIP points at userspace, not kernel text/data or
+ * elsewhere.
+ */
+ if (!__access_ok(pc, instructions_to_print * sizeof(int), USER_DS)) {
+ pr_info("%s[%d]: Bad NIP, not dumping instructions.\n",
+ current->comm, current->pid);
+ return;
+ }
+
pr_info("%s[%d]: code: ", current->comm, current->pid);
for (i = 0; i < instructions_to_print; i++) {