android_kernel_motorola_sm6375/kernel/bpf
Repository files (latest commit first)
Filename Latest commit message Latest commit date
John Fastabend 7c1134c7da bpf: Verifer, adjust_scalar_min_max_vals to always call update_reg_bounds()
commit 294f2fc6da27620a506e6c050241655459ccd6bd upstream.

Currently, for all op verification we call __red_deduce_bounds() and
__red_bound_offset() but we only call __update_reg_bounds() in bitwise
ops. However, we could benefit from calling __update_reg_bounds() in
BPF_ADD, BPF_SUB, and BPF_MUL cases as well.

For example, a register with state 'R1_w=invP0' when we subtract from
it,

 w1 -= 2

Before coerce we will now have an smin_value=S64_MIN, smax_value=U64_MAX
and unsigned bounds umin_value=0, umax_value=U64_MAX. These will then
be clamped to S32_MIN, U32_MAX values by coerce in the case of alu32 op
as done in above example. However tnum will be a constant because the
ALU op is done on a constant.

Without update_reg_bounds() we have a scenario where tnum is a const
but our unsigned bounds do not reflect this. By calling update_reg_bounds
after coerce to 32bit we further refine the umin_value to U64_MAX in the
alu64 case or U32_MAX in the alu32 case above.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158507151689.15666.566796274289413203.stgit@john-Precision-5820-Tower
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-11 12:57:51 +02:00
..
arraymap.c
bpf_lru_list.c bpf_lru_list: Read double-checked variable once without lock 2021-03-04 10:26:16 +01:00
bpf_lru_list.h
btf.c bpf: Explicitly memset some bpf info structures declared on the stack 2020-04-02 15:11:01 +02:00
cgroup.c bpf, cgroup: Fix problematic bounds check 2021-02-10 09:25:27 +01:00
core.c bpf: Make sure mac_header was set before using it 2022-07-29 17:14:16 +02:00
cpumap.c cpumap: Avoid warning when CONFIG_DEBUG_PER_CPU_MAPS is enabled 2020-05-02 08:48:51 +02:00
devmap.c bpf: Fix integer overflow in argument calculation for bpf_map_area_alloc 2021-12-17 10:12:24 +01:00
disasm.c bpf: Introduce BPF nospec instruction for mitigating Spectre v4 2021-09-15 09:47:38 +02:00
disasm.h
hashtab.c bpf: Zero-fill re-used per-cpu map element 2020-11-18 19:20:26 +01:00
helpers.c bpf: Fix helper bpf_map_peek_elem_proto pointing to wrong callback 2021-01-23 15:57:56 +01:00
inode.c bpf: Fix a rcu warning for bpffs map pretty-print 2020-10-01 13:18:19 +02:00
local_storage.c
lpm_trie.c
Makefile bpf: Don't rely on GCC __attribute__((optimize)) to disable GCSE 2020-11-18 19:20:26 +01:00
map_in_map.c
map_in_map.h
offload.c
percpu_freelist.c
percpu_freelist.h
queue_stack_maps.c
reuseport_array.c
stackmap.c bpf: Fix incorrect memory charge cost calculation in stack_map_alloc() 2022-06-22 14:11:02 +02:00
syscall.c bpf: Add kconfig knob for disabling unpriv bpf by default 2022-02-16 12:52:49 +01:00
sysfs_btf.c bpf: Fix sysfs export of empty BTF section 2020-10-14 10:32:58 +02:00
tnum.c
verifier.c bpf: Verifer, adjust_scalar_min_max_vals to always call update_reg_bounds() 2022-08-11 12:57:51 +02:00
xskmap.c