linux/arch/arm64/net
Puranjay Mohan 19d3c179a3 bpf, arm64: Fix trampoline for BPF_TRAMP_F_CALL_ORIG
When BPF_TRAMP_F_CALL_ORIG is set, the trampoline calls
__bpf_tramp_enter() and __bpf_tramp_exit() functions, passing them
the struct bpf_tramp_image *im pointer as an argument in R0.

The trampoline generation code uses emit_addr_mov_i64() to emit
instructions for moving the bpf_tramp_image address into R0, but
emit_addr_mov_i64() assumes the address to be in the vmalloc() space
and uses only 48 bits. Because bpf_tramp_image is allocated using
kzalloc(), its address can use more than 48-bits, in this case the
trampoline will pass an invalid address to __bpf_tramp_enter/exit()
causing a kernel crash.

Fix this by using emit_a64_mov_i64() in place of emit_addr_mov_i64()
as it can work with addresses that are greater than 48-bits.

Fixes: efc9909fdc ("bpf, arm64: Add bpf trampoline for arm64")
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Closes: https://lore.kernel.org/all/SJ0PR15MB461564D3F7E7A763498CA6A8CBDB2@SJ0PR15MB4615.namprd15.prod.outlook.com/
Link: https://lore.kernel.org/bpf/20240711151838.43469-1-puranjay@kernel.org
2024-07-11 17:56:30 +02:00
..
bpf_jit_comp.c bpf, arm64: Fix trampoline for BPF_TRAMP_F_CALL_ORIG 2024-07-11 17:56:30 +02:00
bpf_jit.h bpf, arm64: inline bpf_get_smp_processor_id() helper 2024-05-12 16:54:34 -07:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00