On Wed, Jun 09, 2021 at 03:12:11PM -0700, Vineet Gupta wrote: > Currently enabling this triggers a warning > > | usercopy: Kernel memory overwrite attempt detected to kernel text (offset > 155633, size 11)! > | usercopy: BUG: failure at mm/usercopy.c:99/usercopy_abort()! > | > |gcc generated __builtin_trap > |Path: /bin/busybox > |CPU: 0 PID: 84 Comm: init Not tainted 5.4.22 > | > |[ECR ]: 0x00090005 => gcc generated __builtin_trap > |[EFA ]: 0x9024fcaa > |[BLINK ]: usercopy_abort+0x8a/0x8c > |[ERET ]: memfd_fcntl+0x0/0x470 > |[STAT32]: 0x80080802 : IE K > |BTA: 0x901ba38c SP: 0xbe161ecc FP: 0xbf9fe950 > |LPS: 0x90677408 LPE: 0x9067740c LPC: 0x00000000 > |r00: 0x0000003c r01: 0xbf0ed280 r02: 0x00000000 > |r03: 0xbe15fa30 r04: 0x00d2803e r05: 0x00000000 > |r06: 0x675d7000 r07: 0x00000000 r08: 0x675d9c00 > |r09: 0x00000000 r10: 0x0000035c r11: 0x61206572 > |r12: 0x9024fcaa r13: 0x0000000b r14: 0x0000000b > |r15: 0x00000000 r16: 0x90169ffc r17: 0x90168000 > |r18: 0x00000000 r19: 0xbf092010 r20: 0x00000001 > |r21: 0x00000011 r22: 0x5ffffff1 r23: 0x90169ff1 > |r24: 0xbe196c00 r25: 0xbf0ed280 > | > |Stack Trace: > | memfd_fcntl+0x0/0x470 > | usercopy_abort+0x8a/0x8c > | __check_object_size+0x10e/0x138 > | copy_strings+0x1f4/0x38c > | __do_execve_file+0x352/0x848 > | EV_Trap+0xcc/0xd0
What was the root cause here? Was it that the init section gets freed and reused for kmalloc? > > Fixes: https://github.com/foss-for-synopsys-dwc-arc-processors/linux/issues/15 > Reported-by: Evgeniy Didin <di...@synopsys.com> > Signed-off-by: Vineet Gupta <vgu...@synopsys.com> > --- > arch/arc/kernel/vmlinux.lds.S | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arc/kernel/vmlinux.lds.S b/arch/arc/kernel/vmlinux.lds.S > index 33ce59d91461..e2146a8da195 100644 > --- a/arch/arc/kernel/vmlinux.lds.S > +++ b/arch/arc/kernel/vmlinux.lds.S > @@ -57,7 +57,6 @@ SECTIONS > .init.ramfs : { INIT_RAM_FS } > > . = ALIGN(PAGE_SIZE); > - _stext = .; > > HEAD_TEXT_SECTION > INIT_TEXT_SECTION(L1_CACHE_BYTES) > @@ -83,6 +82,7 @@ SECTIONS > > .text : { > _text = .; > + _stext = .; > TEXT_TEXT > SCHED_TEXT > CPUIDLE_TEXT > -- > 2.25.1 > -- Kees Cook _______________________________________________ linux-snps-arc mailing list linux-snps-arc@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-snps-arc
