X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=lttng-filter-interpreter.c;h=5d5724379749a00a8a80fd042b770a59c950e5a4;hb=2ce89d35c9477d8c17c00489c72e1548e16af9b9;hp=5bf0bd6074719ef59cf5dc8a2fe57f4cc0f5e7e7;hpb=e16c054bb621df50a1710dcd9d1d613f13ef52d2;p=lttng-modules.git diff --git a/lttng-filter-interpreter.c b/lttng-filter-interpreter.c index 5bf0bd60..5d572437 100644 --- a/lttng-filter-interpreter.c +++ b/lttng-filter-interpreter.c @@ -1,31 +1,14 @@ -/* +/* SPDX-License-Identifier: MIT + * * lttng-filter-interpreter.c * * LTTng modules filter interpreter. * * Copyright (C) 2010-2016 Mathieu Desnoyers - * - * Permission is hereby granted, free of charge, to any person obtaining a copy - * of this software and associated documentation files (the "Software"), to deal - * in the Software without restriction, including without limitation the rights - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - * copies of the Software, and to permit persons to whom the Software is - * furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice shall be included in - * all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE - * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE - * SOFTWARE. */ -#include -#include +#include +#include #include #include @@ -47,7 +30,7 @@ char get_char(struct estack_entry *reg, size_t offset) char c; /* Handle invalid access as end of string. */ - if (unlikely(!access_ok(VERIFY_READ, + if (unlikely(!lttng_access_ok(VERIFY_READ, reg->u.s.user_str + offset, sizeof(c)))) return '\0'; @@ -98,16 +81,14 @@ static int stack_star_glob_match(struct estack *stack, int top, const char *cmp_type) { bool has_user = false; - mm_segment_t old_fs; int result; struct estack_entry *pattern_reg; struct estack_entry *candidate_reg; + /* Disable the page fault handler when reading from userspace. */ if (estack_bx(stack, top)->u.s.user || estack_ax(stack, top)->u.s.user) { has_user = true; - old_fs = get_fs(); - set_fs(KERNEL_DS); pagefault_disable(); } @@ -123,10 +104,8 @@ int stack_star_glob_match(struct estack *stack, int top, const char *cmp_type) /* Perform the match operation. */ result = !strutils_star_glob_match_char_cb(get_char_at_cb, pattern_reg, get_char_at_cb, candidate_reg); - if (has_user) { + if (has_user) pagefault_enable(); - set_fs(old_fs); - } return result; } @@ -136,13 +115,10 @@ int stack_strcmp(struct estack *stack, int top, const char *cmp_type) { size_t offset_bx = 0, offset_ax = 0; int diff, has_user = 0; - mm_segment_t old_fs; if (estack_bx(stack, top)->u.s.user || estack_ax(stack, top)->u.s.user) { has_user = 1; - old_fs = get_fs(); - set_fs(KERNEL_DS); pagefault_disable(); } @@ -227,10 +203,9 @@ int stack_strcmp(struct estack *stack, int top, const char *cmp_type) offset_bx++; offset_ax++; } - if (has_user) { + if (has_user) pagefault_enable(); - set_fs(old_fs); - } + return diff; } @@ -572,7 +547,7 @@ static int dynamic_load_field(struct estack_entry *stack_top) ret = -EINVAL; goto end; } - stack_top->u.s.seq_len = SIZE_MAX; + stack_top->u.s.seq_len = LTTNG_SIZE_MAX; stack_top->u.s.literal_type = ESTACK_STRING_LITERAL_TYPE_NONE; break; @@ -771,6 +746,8 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data, [ FILTER_OP_LOAD_FIELD_DOUBLE ] = &&LABEL_FILTER_OP_LOAD_FIELD_DOUBLE, [ FILTER_OP_UNARY_BIT_NOT ] = &&LABEL_FILTER_OP_UNARY_BIT_NOT, + + [ FILTER_OP_RETURN_S64 ] = &&LABEL_FILTER_OP_RETURN_S64, }; #endif /* #ifndef INTERPRETER_USE_SWITCH */ @@ -788,6 +765,7 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data, goto end; OP(FILTER_OP_RETURN): + OP(FILTER_OP_RETURN_S64): /* LTTNG_FILTER_DISCARD or LTTNG_FILTER_RECORD_FLAG */ retval = !!estack_ax_v; ret = 0; @@ -990,7 +968,12 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data, { int64_t res; - res = (estack_bx_v >> estack_ax_v); + /* Catch undefined behavior. */ + if (unlikely(estack_ax_v < 0 || estack_ax_v >= 64)) { + ret = -EINVAL; + goto end; + } + res = ((uint64_t) estack_bx_v >> (uint32_t) estack_ax_v); estack_pop(stack, top, ax, bx); estack_ax_v = res; next_pc += sizeof(struct binary_op); @@ -1000,7 +983,12 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data, { int64_t res; - res = (estack_bx_v << estack_ax_v); + /* Catch undefined behavior. */ + if (unlikely(estack_ax_v < 0 || estack_ax_v >= 64)) { + ret = -EINVAL; + goto end; + } + res = ((uint64_t) estack_bx_v << (uint32_t) estack_ax_v); estack_pop(stack, top, ax, bx); estack_ax_v = res; next_pc += sizeof(struct binary_op); @@ -1010,7 +998,7 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data, { int64_t res; - res = (estack_bx_v & estack_ax_v); + res = ((uint64_t) estack_bx_v & (uint64_t) estack_ax_v); estack_pop(stack, top, ax, bx); estack_ax_v = res; next_pc += sizeof(struct binary_op); @@ -1020,7 +1008,7 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data, { int64_t res; - res = (estack_bx_v | estack_ax_v); + res = ((uint64_t) estack_bx_v | (uint64_t) estack_ax_v); estack_pop(stack, top, ax, bx); estack_ax_v = res; next_pc += sizeof(struct binary_op); @@ -1030,7 +1018,7 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data, { int64_t res; - res = (estack_bx_v ^ estack_ax_v); + res = ((uint64_t) estack_bx_v ^ (uint64_t) estack_ax_v); estack_pop(stack, top, ax, bx); estack_ax_v = res; next_pc += sizeof(struct binary_op); @@ -1049,7 +1037,7 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data, OP(FILTER_OP_UNARY_BIT_NOT): { - estack_ax_v = ~estack_ax_v; + estack_ax_v = ~(uint64_t) estack_ax_v; next_pc += sizeof(struct unary_op); PO; } @@ -1546,7 +1534,7 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data, ret = -EINVAL; goto end; } - estack_ax(stack, top)->u.s.seq_len = SIZE_MAX; + estack_ax(stack, top)->u.s.seq_len = LTTNG_SIZE_MAX; estack_ax(stack, top)->u.s.literal_type = ESTACK_STRING_LITERAL_TYPE_NONE; next_pc += sizeof(struct load_op);