: __clobber_all);
}
+/* Registers r{0,1,2} share same ID when 'if r1 > ...' insn is processed,
+ * check that verifier marks r{1,2} as precise while backtracking
+ * 'if r1 > ...' with r0 already marked.
+ */
+SEC("socket")
+__success __log_level(2)
+__flag(BPF_F_TEST_STATE_FREQ)
+__msg("frame0: regs=r0 stack= before 5: (2d) if r1 > r3 goto pc+0")
+__msg("frame0: parent state regs=r0,r1,r2,r3 stack=:")
+__msg("frame0: regs=r0,r1,r2,r3 stack= before 4: (b7) r3 = 7")
+__naked void linked_regs_bpf_x_src(void)
+{
+ asm volatile (
+ /* r0 = random number up to 0xff */
+ "call %[bpf_ktime_get_ns];"
+ "r0 &= 0xff;"
+ /* tie r0.id == r1.id == r2.id */
+ "r1 = r0;"
+ "r2 = r0;"
+ "r3 = 7;"
+ "if r1 > r3 goto +0;"
+ /* force r0 to be precise, this eventually marks r1 and r2 as
+ * precise as well because of shared IDs
+ */
+ "r4 = r10;"
+ "r4 += r0;"
+ "r0 = 0;"
+ "exit;"
+ :
+ : __imm(bpf_ktime_get_ns)
+ : __clobber_all);
+}
+
+/* Registers r{0,1,2} share same ID when 'if r1 > r3' insn is processed,
+ * check that verifier marks r{0,1,2} as precise while backtracking
+ * 'if r1 > r3' with r3 already marked.
+ */
+SEC("socket")
+__success __log_level(2)
+__flag(BPF_F_TEST_STATE_FREQ)
+__msg("frame0: regs=r3 stack= before 5: (2d) if r1 > r3 goto pc+0")
+__msg("frame0: parent state regs=r0,r1,r2,r3 stack=:")
+__msg("frame0: regs=r0,r1,r2,r3 stack= before 4: (b7) r3 = 7")
+__naked void linked_regs_bpf_x_dst(void)
+{
+ asm volatile (
+ /* r0 = random number up to 0xff */
+ "call %[bpf_ktime_get_ns];"
+ "r0 &= 0xff;"
+ /* tie r0.id == r1.id == r2.id */
+ "r1 = r0;"
+ "r2 = r0;"
+ "r3 = 7;"
+ "if r1 > r3 goto +0;"
+ /* force r0 to be precise, this eventually marks r1 and r2 as
+ * precise as well because of shared IDs
+ */
+ "r4 = r10;"
+ "r4 += r3;"
+ "r0 = 0;"
+ "exit;"
+ :
+ : __imm(bpf_ktime_get_ns)
+ : __clobber_all);
+}
+
/* Same as linked_regs_bpf_k, but break one of the
* links, note that r1 is absent from regs=... in __msg below.
*/
: __clobber_all);
}
+SEC("socket")
+__success __log_level(2)
+__flag(BPF_F_TEST_STATE_FREQ)
+/* check thar r0 and r6 have different IDs after 'if',
+ * collect_linked_regs() can't tie more than 6 registers for a single insn.
+ */
+__msg("8: (25) if r0 > 0x7 goto pc+0 ; R0=scalar(id=1")
+__msg("9: (bf) r6 = r6 ; R6_w=scalar(id=2")
+/* check that r{0-5} are marked precise after 'if' */
+__msg("frame0: regs=r0 stack= before 8: (25) if r0 > 0x7 goto pc+0")
+__msg("frame0: parent state regs=r0,r1,r2,r3,r4,r5 stack=:")
+__naked void linked_regs_too_many_regs(void)
+{
+ asm volatile (
+ /* r0 = random number up to 0xff */
+ "call %[bpf_ktime_get_ns];"
+ "r0 &= 0xff;"
+ /* tie r{0-6} IDs */
+ "r1 = r0;"
+ "r2 = r0;"
+ "r3 = r0;"
+ "r4 = r0;"
+ "r5 = r0;"
+ "r6 = r0;"
+ /* propagate range for r{0-6} */
+ "if r0 > 7 goto +0;"
+ /* make r6 appear in the log */
+ "r6 = r6;"
+ /* force r0 to be precise,
+ * this would cause r{0-4} to be precise because of shared IDs
+ */
+ "r7 = r10;"
+ "r7 += r0;"
+ "r0 = 0;"
+ "exit;"
+ :
+ : __imm(bpf_ktime_get_ns)
+ : __clobber_all);
+}
+
+SEC("socket")
+__failure __log_level(2)
+__flag(BPF_F_TEST_STATE_FREQ)
+__msg("regs=r7 stack= before 5: (3d) if r8 >= r0")
+__msg("parent state regs=r0,r7,r8")
+__msg("regs=r0,r7,r8 stack= before 4: (25) if r0 > 0x1")
+__msg("div by zero")
+__naked void linked_regs_broken_link_2(void)
+{
+ asm volatile (
+ "call %[bpf_get_prandom_u32];"
+ "r7 = r0;"
+ "r8 = r0;"
+ "call %[bpf_get_prandom_u32];"
+ "if r0 > 1 goto +0;"
+ /* r7.id == r8.id,
+ * thus r7 precision implies r8 precision,
+ * which implies r0 precision because of the conditional below.
+ */
+ "if r8 >= r0 goto 1f;"
+ /* break id relation between r7 and r8 */
+ "r8 += r8;"
+ /* make r7 precise */
+ "if r7 == 0 goto 1f;"
+ "r0 /= 0;"
+"1:"
+ "r0 = 42;"
+ "exit;"
+ :
+ : __imm(bpf_get_prandom_u32)
+ : __clobber_all);
+}
+
+/* Check that mark_chain_precision() for one of the conditional jump
+ * operands does not trigger equal scalars precision propagation.
+ */
+SEC("socket")
+__success __log_level(2)
+__msg("3: (25) if r1 > 0x100 goto pc+0")
+__msg("frame0: regs=r1 stack= before 2: (bf) r1 = r0")
+__naked void cjmp_no_linked_regs_trigger(void)
+{
+ asm volatile (
+ /* r0 = random number up to 0xff */
+ "call %[bpf_ktime_get_ns];"
+ "r0 &= 0xff;"
+ /* tie r0.id == r1.id */
+ "r1 = r0;"
+ /* the jump below would be predicted, thus r1 would be marked precise,
+ * this should not imply precision mark for r0
+ */
+ "if r1 > 256 goto +0;"
+ "r0 = 0;"
+ "exit;"
+ :
+ : __imm(bpf_ktime_get_ns)
+ : __clobber_all);
+}
+
/* Verify that check_ids() is used by regsafe() for scalars.
*
* r9 = ... some pointer with range X ...