Package: libc6-dev Version: 2.7-16 Severity: normal File: /usr/include/regexp.h According to SUSv2, compile() defined in <regexp.h> must invoke RETURN(ptr) if it succeeds or ERROR(val) if it fails. The current implementation in glibc violates the standard in two ways: (1) It often invokes RETURN in error situations. For example, it maps REG_EBRACE to RETURN(44). That should be ERROR(44) instead. (2) If it succeeds, it invokes RETURN with a pointer that points outside the buffer provided by the caller. It should have placed the compiled regexp object at the beginning of the buffer and given to RETURN a pointer just beyond the end of the object. SUSv2 says the pointer is useful for memory allocation; presumably, an application could use the remaining part of the buffer for other purposes. The application cannot do that when the pointer points somewhere else entirely. It seems compile() actually sets up __expr_ptr->buffer and __expr_ptr->allocated in order to tell regcomp() where it should place the compiled data, but regcomp() then clears those members right away and allocates its own buffer. With bugs like this, it may be better to remove <regexp.h> than fix it.
#include <stdio.h> static char *arg_of_RETURN; static int arg_of_ERROR; static int fail; static char is_RETURN; static char is_ERROR; #define INIT const unsigned char *re = (unsigned char *) instring; #define GETC() (*re++) #define PEEKC() (*re) #define UNGETC(c) \ do { \ int ch = (c); \ --re; \ if (ch != *re) { \ printf("FAIL: UNGETC(%d) expected %d\n", \ ch, *re); \ fail++; \ } \ } while (0) #define RETURN(ptr) return (arg_of_RETURN = (ptr), arg_of_ERROR = 0, &is_RETURN) #define ERROR(val) return (arg_of_RETURN = NULL, arg_of_ERROR = (val), &is_ERROR) #include <regexp.h> int main(void) { enum { buflen = 100000 }; char expbuf[buflen]; char *ptr; int totalfail = 0; printf("TEST: compile regexp to one-byte buffer\n"); fail = 0; ptr = compile("tropelet", expbuf, expbuf + 1, 'e'); if (ptr != &is_ERROR) { printf("FAIL: compile did not use ERROR\n"); fail++; } else if (arg_of_ERROR != 50) { printf("FAIL: compile used ERROR(%d), not ERROR(50)\n", arg_of_ERROR); fail++; } if (fail) totalfail++; else printf("OK\n"); printf("TEST: compile regexp to large buffer\n"); fail = 0; ptr = compile("tropelet", expbuf, expbuf + buflen, 'e'); if (ptr != &is_RETURN) { printf("FAIL: compile did not use RETURN\n"); fail++; } else if (arg_of_RETURN < expbuf || arg_of_RETURN > expbuf + buflen) { printf("FAIL: compile used RETURN(%p) which does not point into expbuf\n", (void *) arg_of_RETURN); fail++; } if (fail) totalfail++; else printf("OK\n"); printf("TEST: compile regexp with too many numbers in \\{\\}\n"); fail = 0; ptr = compile("z\\{1,2,3\\}", expbuf, expbuf + buflen, '\0'); if (ptr != &is_ERROR) { printf("FAIL: compile did not use ERROR\n"); fail++; } else if (arg_of_ERROR != 44) { printf("FAIL: compile used ERROR(%d), not ERROR(44)\n", arg_of_ERROR); fail++; } if (fail) totalfail++; else printf("OK\n"); return totalfail ? EXIT_FAILURE : EXIT_SUCCESS; }
-- System Information: Debian Release: lenny/sid APT prefers unstable APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental') Architecture: i386 (i686) Shell: /bin/sh linked to /bin/bash Kernel: Linux 2.6.26-1-686 Locale: LANG=fi_FI.UTF-8, LC_CTYPE=fi_FI.UTF-8 (charmap=UTF-8) Versions of packages libc6-dev depends on: ii libc6 2.7-16 GNU C Library: Shared libraries ii linux-libc-dev 2.6.26-9.kon.1 Linux support headers for userspac Versions of packages libc6-dev recommends: ii gcc [c-compiler] 4:4.3.1-2 The GNU C compiler ii gcc-3.3 [c-compiler] 1:3.3.5-12 The GNU C compiler ii gcc-3.4 [c-compiler] 3.4.6-1 The GNU C compiler ii gcc-4.0 [c-compiler] 4.0.3-3 The GNU C compiler ii gcc-4.1 [c-compiler] 4.1.2-22 The GNU C compiler ii gcc-4.2 [c-compiler] 4.2.4-3 The GNU C compiler ii gcc-4.3 [c-compiler] 4.3.1-4 The GNU C compiler ii tcc [c-compiler] 0.9.24-1 the smallest ANSI C compiler -- no debconf information
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