Function report

Linux Kernel

v5.5.9

Brick Technologies Co., Ltd

Source Code:kernel\bpf\verifier.c Create Date:2022-07-28 12:56:35
Last Modify:2022-05-19 20:02:10 Copyright©Brick
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Name:Uses signed min/max values to inform unsigned, and vice-versa

Proto:static void __reg_deduce_bounds(struct bpf_reg_state *reg)

Type:void

Parameter:

TypeParameterName
struct bpf_reg_state *reg
1002  If minimum possible (s64)value >= 0 || maximum possible (s64)value < 0 Then
1003  minimum possible (s64)value = minimum possible (u64)value = max_t - return maximum of two values, using the specified type*@type: data type to use*@x: first value*@y: second value(u64, minimum possible (s64)value , minimum possible (u64)value )
1005  maximum possible (s64)value = maximum possible (u64)value = min_t - return minimum of two values, using the specified type*@type: data type to use*@x: first value*@y: second value(u64, maximum possible (s64)value , maximum possible (u64)value )
1007  Return
1012  If maximum possible (u64)value >= 0 Then
1016  minimum possible (s64)value = minimum possible (u64)value
1017  maximum possible (s64)value = maximum possible (u64)value = min_t - return minimum of two values, using the specified type*@type: data type to use*@x: first value*@y: second value(u64, maximum possible (s64)value , maximum possible (u64)value )
1019  Else if minimum possible (u64)value < 0 Then
1023  minimum possible (s64)value = minimum possible (u64)value = max_t - return maximum of two values, using the specified type*@type: data type to use*@x: first value*@y: second value(u64, minimum possible (s64)value , minimum possible (u64)value )
1025  maximum possible (s64)value = maximum possible (u64)value
Caller
NameDescribe
do_refine_retval_range
adjust_ptr_min_max_valsHandles arithmetic on a pointer and a scalar: computes new min/max and var_off.* Caller should also handle BPF_MOV case separately.* If we return -EACCES, caller may want to try again treating pointer as a* scalar
adjust_scalar_min_max_valsWARNING: This function does calculations on 64-bit values, but the actual* execution may occur on 32-bit values. Therefore, things like bitshifts* need extra checks in the 32-bit case.
reg_set_min_maxAdjusts the register min/max values in the case that the dst_reg is the* variable register that we are working on, and src_reg is a constant or we're* simply doing a BPF_K check.* In JEQ/JNE cases we also adjust the var_off values.
reg_set_min_max_invSame as above, but for the case that dst_reg holds a constant and src_reg is* the variable reg.
__reg_combine_min_maxRegs are known to be equal, so intersect their min/max/var_off