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authorOlof Johansson <olof@lixom.net>2022-01-05 16:18:44 -0800
committerOlof Johansson <olof@lixom.net>2022-01-05 16:18:50 -0800
commit8922bb6526ac4b20bd8de7f47d6e77808670f6c4 (patch)
tree476cd8a432272c29b8a67e679c0aa65e0a12b28e /kernel/bpf/verifier.c
parentfde9ec3c1b3dd361bff62fc89d95d03df51a0648 (diff)
parent36de991e93908f7ad5c2a0eac9c4ecf8b723fa4a (diff)
Merge tag 'socfpga_fix_for_v5.16_part_3' of git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux into arm/fixes
SoCFPGA dts updates for v5.16, part 3 - Change the SoCFPGA compatible to "intel,socfpga-qspi" - Update dt-bindings document to include "intel,socfpga-qspi" * tag 'socfpga_fix_for_v5.16_part_3' of git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux: (361 commits) ARM: dts: socfpga: change qspi to "intel,socfpga-qspi" dt-bindings: spi: cadence-quadspi: document "intel,socfpga-qspi" Linux 5.16-rc7 mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() mm/damon/dbgfs: protect targets destructions with kdamond_lock mm/page_alloc: fix __alloc_size attribute for alloc_pages_exact_nid mm: delete unsafe BUG from page_cache_add_speculative() mm, hwpoison: fix condition in free hugetlb page path MAINTAINERS: mark more list instances as moderated kernel/crash_core: suppress unknown crashkernel parameter warning mm: mempolicy: fix THP allocations escaping mempolicy restrictions kfence: fix memory leak when cat kfence objects platform/x86: intel_pmc_core: fix memleak on registration failure net: stmmac: dwmac-visconti: Fix value of ETHER_CLK_SEL_FREQ_SEL_2P5M r8152: sync ocp base r8152: fix the force speed doesn't work for RTL8156 net: bridge: fix ioctl old_deviceless bridge argument net: stmmac: ptp: fix potentially overflowing expression net: dsa: tag_ocelot: use traffic class to map priority on injected header veth: ensure skb entering GRO are not cloned. ... Link: https://lore.kernel.org/r/20211227103644.566694-1-dinguyen@kernel.org Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'kernel/bpf/verifier.c')
-rw-r--r--kernel/bpf/verifier.c53
1 files changed, 36 insertions, 17 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index f3001937bbb9..b532f1058d35 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1366,22 +1366,28 @@ static void __reg_bound_offset(struct bpf_reg_state *reg)
reg->var_off = tnum_or(tnum_clear_subreg(var64_off), var32_off);
}
+static bool __reg32_bound_s64(s32 a)
+{
+ return a >= 0 && a <= S32_MAX;
+}
+
static void __reg_assign_32_into_64(struct bpf_reg_state *reg)
{
reg->umin_value = reg->u32_min_value;
reg->umax_value = reg->u32_max_value;
- /* Attempt to pull 32-bit signed bounds into 64-bit bounds
- * but must be positive otherwise set to worse case bounds
- * and refine later from tnum.
+
+ /* Attempt to pull 32-bit signed bounds into 64-bit bounds but must
+ * be positive otherwise set to worse case bounds and refine later
+ * from tnum.
*/
- if (reg->s32_min_value >= 0 && reg->s32_max_value >= 0)
- reg->smax_value = reg->s32_max_value;
- else
- reg->smax_value = U32_MAX;
- if (reg->s32_min_value >= 0)
+ if (__reg32_bound_s64(reg->s32_min_value) &&
+ __reg32_bound_s64(reg->s32_max_value)) {
reg->smin_value = reg->s32_min_value;
- else
+ reg->smax_value = reg->s32_max_value;
+ } else {
reg->smin_value = 0;
+ reg->smax_value = U32_MAX;
+ }
}
static void __reg_combine_32_into_64(struct bpf_reg_state *reg)
@@ -2379,8 +2385,6 @@ static int backtrack_insn(struct bpf_verifier_env *env, int idx,
*/
if (insn->src_reg != BPF_REG_FP)
return 0;
- if (BPF_SIZE(insn->code) != BPF_DW)
- return 0;
/* dreg = *(u64 *)[fp - off] was a fill from the stack.
* that [fp - off] slot contains scalar that needs to be
@@ -2403,8 +2407,6 @@ static int backtrack_insn(struct bpf_verifier_env *env, int idx,
/* scalars can only be spilled into stack */
if (insn->dst_reg != BPF_REG_FP)
return 0;
- if (BPF_SIZE(insn->code) != BPF_DW)
- return 0;
spi = (-insn->off - 1) / BPF_REG_SIZE;
if (spi >= 64) {
verbose(env, "BUG spi %d\n", spi);
@@ -4551,9 +4553,16 @@ static int check_atomic(struct bpf_verifier_env *env, int insn_idx, struct bpf_i
if (insn->imm == BPF_CMPXCHG) {
/* Check comparison of R0 with memory location */
- err = check_reg_arg(env, BPF_REG_0, SRC_OP);
+ const u32 aux_reg = BPF_REG_0;
+
+ err = check_reg_arg(env, aux_reg, SRC_OP);
if (err)
return err;
+
+ if (is_pointer_value(env, aux_reg)) {
+ verbose(env, "R%d leaks addr into mem\n", aux_reg);
+ return -EACCES;
+ }
}
if (is_pointer_value(env, insn->src_reg)) {
@@ -4588,13 +4597,19 @@ static int check_atomic(struct bpf_verifier_env *env, int insn_idx, struct bpf_i
load_reg = -1;
}
- /* check whether we can read the memory */
+ /* Check whether we can read the memory, with second call for fetch
+ * case to simulate the register fill.
+ */
err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
- BPF_SIZE(insn->code), BPF_READ, load_reg, true);
+ BPF_SIZE(insn->code), BPF_READ, -1, true);
+ if (!err && load_reg >= 0)
+ err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
+ BPF_SIZE(insn->code), BPF_READ, load_reg,
+ true);
if (err)
return err;
- /* check whether we can write into the same memory */
+ /* Check whether we can write into the same memory. */
err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
BPF_SIZE(insn->code), BPF_WRITE, -1, true);
if (err)
@@ -8308,6 +8323,10 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
insn->dst_reg);
}
zext_32_to_64(dst_reg);
+
+ __update_reg_bounds(dst_reg);
+ __reg_deduce_bounds(dst_reg);
+ __reg_bound_offset(dst_reg);
}
} else {
/* case: R = imm