From: Helge Deller deller@gmx.de
commit 59a783dbc0d5fd6792aabff933055373b6dcbf2a upstream.
When running gdb I was able to trigger this kernel panic:
Kernel Fault: Code=26 (Data memory access rights trap) at addr 0000000000000060 CPU: 0 PID: 1401 Comm: gdb-crash Not tainted 5.2.0-rc7-64bit+ #1053
YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI PSW: 00001000000001000000000000001111 Not tainted r00-03 000000000804000f 0000000040dee1a0 0000000040c78cf0 00000000b8d50160 r04-07 0000000040d2b1a0 000000004360a098 00000000bbbe87b8 0000000000000003 r08-11 00000000fac20a70 00000000fac24160 00000000fac1bbe0 0000000000000000 r12-15 00000000fabfb79a 00000000fac244a4 0000000000010000 0000000000000001 r16-19 00000000bbbe87b8 00000000f8f02910 0000000000010034 0000000000000000 r20-23 00000000fac24630 00000000fac24630 000000006474e552 00000000fac1aa52 r24-27 0000000000000028 00000000bbbe87b8 00000000bbbe87b8 0000000040d2b1a0 r28-31 0000000000000000 00000000b8d501c0 00000000b8d501f0 0000000003424000 sr00-03 0000000000423000 0000000000000000 0000000000000000 0000000000423000 sr04-07 0000000000000000 0000000000000000 0000000000000000 0000000000000000
IASQ: 0000000000000000 0000000000000000 IAOQ: 0000000040c78cf0 0000000040c78cf4 IIR: 539f00c0 ISR: 0000000000000000 IOR: 0000000000000060 CPU: 0 CR30: 00000000b8d50000 CR31: 00000000d22345e2 ORIG_R28: 0000000040250798 IAOQ[0]: parisc_kprobe_ss_handler+0x58/0x170 IAOQ[1]: parisc_kprobe_ss_handler+0x5c/0x170 RP(r2): parisc_kprobe_ss_handler+0x58/0x170 Backtrace: [<0000000040206ff8>] handle_interruption+0x178/0xbb8 Kernel panic - not syncing: Kernel Fault
Avoid this panic by checking the return value of kprobe_running() and skip kprobe if none is currently active.
Cc: stable@vger.kernel.org # v5.2 Acked-by: Sven Schnelle svens@stackframe.org Tested-by: Rolf Eike Beer eike-kernel@sf-tec.de Signed-off-by: Helge Deller deller@gmx.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/parisc/kernel/kprobes.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/arch/parisc/kernel/kprobes.c +++ b/arch/parisc/kernel/kprobes.c @@ -133,6 +133,9 @@ int __kprobes parisc_kprobe_ss_handler(s struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); struct kprobe *p = kprobe_running();
+ if (!p) + return 0; + if (regs->iaoq[0] != (unsigned long)p->ainsn.insn+4) return 0;