From afd0be7299533bb2e2b09104399d8a467ecbd2c5 Mon Sep 17 00:00:00 2001 From: Ciara Loftus Date: Thu, 8 Apr 2021 05:20:09 +0000 Subject: libbpf: Fix potential NULL pointer dereference Wait until after the UMEM is checked for null to dereference it. Fixes: 43f1bc1efff1 ("libbpf: Restore umem state after socket create failure") Signed-off-by: Ciara Loftus Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20210408052009.7844-1-ciara.loftus@intel.com --- tools/lib/bpf/xsk.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'tools') diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c index d24b5cc720ec..007fe5d59438 100644 --- a/tools/lib/bpf/xsk.c +++ b/tools/lib/bpf/xsk.c @@ -852,18 +852,19 @@ int xsk_socket__create_shared(struct xsk_socket **xsk_ptr, struct xsk_ring_cons *comp, const struct xsk_socket_config *usr_config) { + bool unmap, rx_setup_done = false, tx_setup_done = false; void *rx_map = NULL, *tx_map = NULL; struct sockaddr_xdp sxdp = {}; struct xdp_mmap_offsets off; struct xsk_socket *xsk; struct xsk_ctx *ctx; int err, ifindex; - bool unmap = umem->fill_save != fill; - bool rx_setup_done = false, tx_setup_done = false; if (!umem || !xsk_ptr || !(rx || tx)) return -EFAULT; + unmap = umem->fill_save != fill; + xsk = calloc(1, sizeof(*xsk)); if (!xsk) return -ENOMEM; -- cgit v1.2.3 From d7a5091351756d0ae8e63134313c455624e36a13 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Wed, 24 Mar 2021 14:52:31 +0100 Subject: bpf: Update selftests to reflect new error states Update various selftest error messages: * The 'Rx tried to sub from different maps, paths, or prohibited types' is reworked into more specific/differentiated error messages for better guidance. * The change into 'value -4294967168 makes map_value pointer be out of bounds' is due to moving the mixed bounds check into the speculation handling and thus occuring slightly later than above mentioned sanity check. * The change into 'math between map_value pointer and register with unbounded min value' is similarly due to register sanity check coming before the mixed bounds check. * The case of 'map access: known scalar += value_ptr from different maps' now loads fine given masks are the same from the different paths (despite max map value size being different). Signed-off-by: Daniel Borkmann Reviewed-by: John Fastabend Acked-by: Alexei Starovoitov --- tools/testing/selftests/bpf/verifier/bounds.c | 5 ----- .../selftests/bpf/verifier/bounds_deduction.c | 21 +++++++++++---------- .../selftests/bpf/verifier/bounds_mix_sign_unsign.c | 13 ------------- tools/testing/selftests/bpf/verifier/map_ptr.c | 4 ++-- tools/testing/selftests/bpf/verifier/unpriv.c | 2 +- .../selftests/bpf/verifier/value_ptr_arith.c | 6 ++---- 6 files changed, 16 insertions(+), 35 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/bpf/verifier/bounds.c b/tools/testing/selftests/bpf/verifier/bounds.c index 57ed67b86074..8a1caf46ffbc 100644 --- a/tools/testing/selftests/bpf/verifier/bounds.c +++ b/tools/testing/selftests/bpf/verifier/bounds.c @@ -261,8 +261,6 @@ }, .fixup_map_hash_8b = { 3 }, /* not actually fully unbounded, but the bound is very high */ - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds, pointer arithmetic with it prohibited for !root", - .result_unpriv = REJECT, .errstr = "value -4294967168 makes map_value pointer be out of bounds", .result = REJECT, }, @@ -298,9 +296,6 @@ BPF_EXIT_INSN(), }, .fixup_map_hash_8b = { 3 }, - /* not actually fully unbounded, but the bound is very high */ - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds, pointer arithmetic with it prohibited for !root", - .result_unpriv = REJECT, .errstr = "value -4294967168 makes map_value pointer be out of bounds", .result = REJECT, }, diff --git a/tools/testing/selftests/bpf/verifier/bounds_deduction.c b/tools/testing/selftests/bpf/verifier/bounds_deduction.c index c162498a64fc..91869aea6d64 100644 --- a/tools/testing/selftests/bpf/verifier/bounds_deduction.c +++ b/tools/testing/selftests/bpf/verifier/bounds_deduction.c @@ -6,7 +6,7 @@ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 has pointer with unsupported alu operation", .errstr = "R0 tried to subtract pointer from scalar", .result = REJECT, }, @@ -21,7 +21,7 @@ BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_0), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R1 tried to sub from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 has pointer with unsupported alu operation", .result_unpriv = REJECT, .result = ACCEPT, .retval = 1, @@ -34,22 +34,23 @@ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 has pointer with unsupported alu operation", .errstr = "R0 tried to subtract pointer from scalar", .result = REJECT, }, { "check deducing bounds from const, 4", .insns = { + BPF_MOV64_REG(BPF_REG_6, BPF_REG_1), BPF_MOV64_IMM(BPF_REG_0, 0), BPF_JMP_IMM(BPF_JSLE, BPF_REG_0, 0, 1), BPF_EXIT_INSN(), BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 1), BPF_EXIT_INSN(), - BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_0), + BPF_ALU64_REG(BPF_SUB, BPF_REG_6, BPF_REG_0), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R1 tried to sub from different maps, paths, or prohibited types", + .errstr_unpriv = "R6 has pointer with unsupported alu operation", .result_unpriv = REJECT, .result = ACCEPT, }, @@ -61,7 +62,7 @@ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 has pointer with unsupported alu operation", .errstr = "R0 tried to subtract pointer from scalar", .result = REJECT, }, @@ -74,7 +75,7 @@ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 has pointer with unsupported alu operation", .errstr = "R0 tried to subtract pointer from scalar", .result = REJECT, }, @@ -88,7 +89,7 @@ offsetof(struct __sk_buff, mark)), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R1 tried to sub from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 has pointer with unsupported alu operation", .errstr = "dereference of modified ctx ptr", .result = REJECT, .flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS, @@ -103,7 +104,7 @@ offsetof(struct __sk_buff, mark)), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 has pointer with unsupported alu operation", .errstr = "dereference of modified ctx ptr", .result = REJECT, .flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS, @@ -116,7 +117,7 @@ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 has pointer with unsupported alu operation", .errstr = "R0 tried to subtract pointer from scalar", .result = REJECT, }, diff --git a/tools/testing/selftests/bpf/verifier/bounds_mix_sign_unsign.c b/tools/testing/selftests/bpf/verifier/bounds_mix_sign_unsign.c index 9baca7a75c42..c2aa6f26738b 100644 --- a/tools/testing/selftests/bpf/verifier/bounds_mix_sign_unsign.c +++ b/tools/testing/selftests/bpf/verifier/bounds_mix_sign_unsign.c @@ -19,7 +19,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -43,7 +42,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -69,7 +67,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R8 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -94,7 +91,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R8 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -141,7 +137,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -210,7 +205,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -260,7 +254,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -287,7 +280,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -313,7 +305,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -342,7 +333,6 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R7 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -372,7 +362,6 @@ }, .fixup_map_hash_8b = { 4 }, .errstr = "unbounded min value", - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds", .result = REJECT, }, { @@ -400,7 +389,5 @@ }, .fixup_map_hash_8b = { 3 }, .errstr = "unbounded min value", - .errstr_unpriv = "R1 has unknown scalar with mixed signed bounds", .result = REJECT, - .result_unpriv = REJECT, }, diff --git a/tools/testing/selftests/bpf/verifier/map_ptr.c b/tools/testing/selftests/bpf/verifier/map_ptr.c index 6f610cfddae5..1f82021429bf 100644 --- a/tools/testing/selftests/bpf/verifier/map_ptr.c +++ b/tools/testing/selftests/bpf/verifier/map_ptr.c @@ -76,7 +76,7 @@ }, .fixup_map_hash_16b = { 4 }, .result_unpriv = REJECT, - .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 has pointer with unsupported alu operation", .result = ACCEPT, }, { @@ -94,6 +94,6 @@ }, .fixup_map_hash_16b = { 4 }, .result_unpriv = REJECT, - .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types", + .errstr_unpriv = "R0 has pointer with unsupported alu operation", .result = ACCEPT, }, diff --git a/tools/testing/selftests/bpf/verifier/unpriv.c b/tools/testing/selftests/bpf/verifier/unpriv.c index 3e32400c4b44..bd436df5cc32 100644 --- a/tools/testing/selftests/bpf/verifier/unpriv.c +++ b/tools/testing/selftests/bpf/verifier/unpriv.c @@ -505,7 +505,7 @@ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8), BPF_EXIT_INSN(), }, - .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types", + .errstr_unpriv = "R1 stack pointer arithmetic goes out of range", .result_unpriv = REJECT, .result = ACCEPT, }, diff --git a/tools/testing/selftests/bpf/verifier/value_ptr_arith.c b/tools/testing/selftests/bpf/verifier/value_ptr_arith.c index feb91266db39..e5913fd3b903 100644 --- a/tools/testing/selftests/bpf/verifier/value_ptr_arith.c +++ b/tools/testing/selftests/bpf/verifier/value_ptr_arith.c @@ -21,8 +21,6 @@ .fixup_map_hash_16b = { 5 }, .fixup_map_array_48b = { 8 }, .result = ACCEPT, - .result_unpriv = REJECT, - .errstr_unpriv = "R1 tried to add from different maps", .retval = 1, }, { @@ -122,7 +120,7 @@ .fixup_map_array_48b = { 1 }, .result = ACCEPT, .result_unpriv = REJECT, - .errstr_unpriv = "R2 tried to add from different pointers or scalars", + .errstr_unpriv = "R2 tried to add from different maps, paths or scalars", .retval = 0, }, { @@ -169,7 +167,7 @@ .fixup_map_array_48b = { 1 }, .result = ACCEPT, .result_unpriv = REJECT, - .errstr_unpriv = "R2 tried to add from different maps, paths, or prohibited types", + .errstr_unpriv = "R2 tried to add from different maps, paths or scalars", .retval = 0, }, { -- cgit v1.2.3