diff options
Diffstat (limited to 'main/musl/0014-fix-missing-integer-overflow-checks-in-regexec-buffe.patch')
-rw-r--r-- | main/musl/0014-fix-missing-integer-overflow-checks-in-regexec-buffe.patch | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/main/musl/0014-fix-missing-integer-overflow-checks-in-regexec-buffe.patch b/main/musl/0014-fix-missing-integer-overflow-checks-in-regexec-buffe.patch new file mode 100644 index 000000000..b35827871 --- /dev/null +++ b/main/musl/0014-fix-missing-integer-overflow-checks-in-regexec-buffe.patch @@ -0,0 +1,73 @@ +From c3edc06d1e1360f3570db9155d6b318ae0d0f0f7 Mon Sep 17 00:00:00 2001 +From: Rich Felker <dalias@aerifal.cx> +Date: Thu, 6 Oct 2016 18:34:58 -0400 +Subject: [PATCH 14/18] fix missing integer overflow checks in regexec buffer + size computations + +most of the possible overflows were already ruled out in practice by +regcomp having already succeeded performing larger allocations. +however at least the num_states*num_tags multiplication can clearly +overflow in practice. for safety, check them all, and use the proper +type, size_t, rather than int. + +also improve comments, use calloc in place of malloc+memset, and +remove bogus casts. +--- + src/regex/regexec.c | 23 ++++++++++++++++++----- + 1 file changed, 18 insertions(+), 5 deletions(-) + +diff --git a/src/regex/regexec.c b/src/regex/regexec.c +index 16c5d0a..dd52319 100644 +--- a/src/regex/regexec.c ++++ b/src/regex/regexec.c +@@ -34,6 +34,7 @@ + #include <wchar.h> + #include <wctype.h> + #include <limits.h> ++#include <stdint.h> + + #include <regex.h> + +@@ -206,11 +207,24 @@ tre_tnfa_run_parallel(const tre_tnfa_t *tnfa, const void *string, + + /* Allocate memory for temporary data required for matching. This needs to + be done for every matching operation to be thread safe. This allocates +- everything in a single large block from the stack frame using alloca() +- or with malloc() if alloca is unavailable. */ ++ everything in a single large block with calloc(). */ + { +- int tbytes, rbytes, pbytes, xbytes, total_bytes; ++ size_t tbytes, rbytes, pbytes, xbytes, total_bytes; + char *tmp_buf; ++ ++ /* Ensure that tbytes and xbytes*num_states cannot overflow, and that ++ * they don't contribute more than 1/8 of SIZE_MAX to total_bytes. */ ++ if (num_tags > SIZE_MAX/(8 * sizeof(int) * tnfa->num_states)) ++ goto error_exit; ++ ++ /* Likewise check rbytes. */ ++ if (tnfa->num_states+1 > SIZE_MAX/(8 * sizeof(*reach_next))) ++ goto error_exit; ++ ++ /* Likewise check pbytes. */ ++ if (tnfa->num_states > SIZE_MAX/(8 * sizeof(*reach_pos))) ++ goto error_exit; ++ + /* Compute the length of the block we need. */ + tbytes = sizeof(*tmp_tags) * num_tags; + rbytes = sizeof(*reach_next) * (tnfa->num_states + 1); +@@ -221,10 +235,9 @@ tre_tnfa_run_parallel(const tre_tnfa_t *tnfa, const void *string, + + (rbytes + xbytes * tnfa->num_states) * 2 + tbytes + pbytes; + + /* Allocate the memory. */ +- buf = xmalloc((unsigned)total_bytes); ++ buf = calloc(total_bytes, 1); + if (buf == NULL) + return REG_ESPACE; +- memset(buf, 0, (size_t)total_bytes); + + /* Get the various pointers within tmp_buf (properly aligned). */ + tmp_tags = (void *)buf; +-- +2.10.1 + |