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Hari Bathini 6f657bb66f powerpc/bpf: Fix write protecting JIT code ... commit 44a8214de9 upstream. Running program with bpf-to-bpf function calls results in data access exception (0x300) with the below call trace: bpf_int_jit_compile+0x238/0x750 (unreliable) bpf_check+0x2008/0x2710 bpf_prog_load+0xb00/0x13a0 __sys_bpf+0x6f4/0x27c0 sys_bpf+0x2c/0x40 system_call_exception+0x164/0x330 system_call_vectored_common+0xe8/0x278 as bpf_int_jit_compile() tries writing to write protected JIT code location during the extra pass. Fix it by holding off write protection of JIT code until the extra pass, where branch target addresses fixup happens. Fixes: 62e3d4210a ("powerpc/bpf: Write protect JIT code") Cc: stable@vger.kernel.org # v5.14+ Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211025055649.114728-1-hbathini@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		History 2021-11-18 19:17:19 +01:00
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bpf_jit.h	powerpc/bpf: Validate branch ranges	2021-10-07 18:52:33 +11:00
bpf_jit64.h	powerpc/bpf: Emit stf barrier instruction sequences for BPF_NOSPEC	2021-10-07 19:52:58 +11:00
bpf_jit_comp.c	powerpc/bpf: Fix write protecting JIT code	2021-11-18 19:17:19 +01:00
bpf_jit_comp32.c	powerpc/bpf ppc32: Fix BPF_SUB when imm == 0x80000000	2021-10-07 19:52:59 +11:00
bpf_jit_comp64.c	powerpc/bpf: Emit stf barrier instruction sequences for BPF_NOSPEC	2021-10-07 19:52:58 +11:00
Makefile	powerpc/bpf: Implement extended BPF on PPC32	2021-04-03 21:22:21 +11:00