diff --git a/src/ascmagic.c b/src/ascmagic.c index 8d6ca95..cfa3951 100644 --- a/src/ascmagic.c +++ b/src/ascmagic.c @@ -147,7 +147,7 @@ file_ascmagic_with_encoding(struct magic_set *ms, const unsigned char *buf, == NULL) goto done; if ((rv = file_softmagic(ms, utf8_buf, - (size_t)(utf8_end - utf8_buf), TEXTTEST, text)) == 0) + (size_t)(utf8_end - utf8_buf), 0, TEXTTEST, text)) == 0) rv = -1; } diff --git a/src/file.h b/src/file.h index 175f659..e02009f 100644 --- a/src/file.h +++ b/src/file.h @@ -414,7 +414,7 @@ protected int file_encoding(struct magic_set *, const unsigned char *, size_t, unichar **, size_t *, const char **, const char **, const char **); protected int file_is_tar(struct magic_set *, const unsigned char *, size_t); protected int file_softmagic(struct magic_set *, const unsigned char *, size_t, - int, int); + size_t, int, int); protected struct mlist *file_apprentice(struct magic_set *, const char *, int); protected uint64_t file_signextend(struct magic_set *, struct magic *, uint64_t); diff --git a/src/funcs.c b/src/funcs.c index 0b2a3d0..0d645eb 100644 --- a/src/funcs.c +++ b/src/funcs.c @@ -228,7 +228,7 @@ file_buffer(struct magic_set *ms, int fd, const char *inname __attribute__ ((unu /* try soft magic tests */ if ((ms->flags & MAGIC_NO_CHECK_SOFT) == 0) - if ((m = file_softmagic(ms, ubuf, nb, BINTEST, + if ((m = file_softmagic(ms, ubuf, nb, 0, BINTEST, looks_text)) != 0) { if ((ms->flags & MAGIC_DEBUG) != 0) (void)fprintf(stderr, "softmagic %d\n", m); diff --git a/src/softmagic.c b/src/softmagic.c index 22e1190..56f09ee 100644 --- a/src/softmagic.c +++ b/src/softmagic.c @@ -41,11 +41,12 @@ FILE_RCSID("@(#)$File: softmagic.c,v 1.147 2011/11/05 15:44:22 rrt Exp $") #include #include +#define OFFSET_OOB(n, o, i) ((n) < (o) || (i) >= ((n) - (o))) private int match(struct magic_set *, struct magic *, uint32_t, - const unsigned char *, size_t, int, int); + const unsigned char *, size_t, int, int, int); private int mget(struct magic_set *, const unsigned char *, - struct magic *, size_t, unsigned int, int); + struct magic *, size_t, unsigned int, int, int); private int magiccheck(struct magic_set *, struct magic *); private int32_t mprint(struct magic_set *, struct magic *); private int32_t moffset(struct magic_set *, struct magic *); @@ -67,13 +68,13 @@ private void cvt_64(union VALUETYPE *, const struct magic *); /*ARGSUSED1*/ /* nbytes passed for regularity, maybe need later */ protected int file_softmagic(struct magic_set *ms, const unsigned char *buf, size_t nbytes, - int mode, int text) + size_t level, int mode, int text) { struct mlist *ml; int rv; for (ml = ms->mlist->next; ml != ms->mlist; ml = ml->next) if ((rv = match(ms, ml->magic, ml->nmagic, buf, nbytes, mode, - text)) != 0) + text, level)) != 0) return rv; return 0; @@ -108,7 +109,8 @@ file_softmagic(struct magic_set *ms, const unsigned char *buf, size_t nbytes, */ private int match(struct magic_set *ms, struct magic *magic, uint32_t nmagic, - const unsigned char *s, size_t nbytes, int mode, int text) + const unsigned char *s, size_t nbytes, int mode, int text, + int recursion_level) { uint32_t magindex = 0; unsigned int cont_level = 0; @@ -140,7 +142,7 @@ match(struct magic_set *ms, struct magic *magic, uint32_t nmagic, ms->line = m->lineno; /* if main entry matches, print it... */ - switch (mget(ms, s, m, nbytes, cont_level, text)) { + switch (mget(ms, s, m, nbytes, cont_level, text, recursion_level + 1)) { case -1: return -1; case 0: @@ -223,7 +225,7 @@ match(struct magic_set *ms, struct magic *magic, uint32_t nmagic, continue; } #endif - switch (mget(ms, s, m, nbytes, cont_level, text)) { + switch (mget(ms, s, m, nbytes, cont_level, text, recursion_level + 1)) { case -1: return -1; case 0: @@ -1018,12 +1020,18 @@ mcopy(struct magic_set *ms, union VALUETYPE *p, int type, int indir, private int mget(struct magic_set *ms, const unsigned char *s, - struct magic *m, size_t nbytes, unsigned int cont_level, int text) + struct magic *m, size_t nbytes, unsigned int cont_level, int text, + int recursion_level) { uint32_t offset = ms->offset; uint32_t count = m->str_range; union VALUETYPE *p = &ms->ms_value; + if (recursion_level >= 20) { + file_error(ms, 0, "recursion nesting exceeded"); + return -1; + } + if (mcopy(ms, p, m->type, m->flag & INDIR, s, offset, nbytes, count) == -1) return -1; @@ -1580,10 +1588,12 @@ mget(struct magic_set *ms, const unsigned char *s, if ((ms->flags & (MAGIC_MIME|MAGIC_APPLE)) == 0 && file_printf(ms, "%s", m->desc) == -1) return -1; - if (nbytes < offset) + if (offset == 0) return 0; + if (OFFSET_OOB(nbytes, offset, 0)) + return 0; return file_softmagic(ms, s + offset, nbytes - offset, - BINTEST, text); + recursion_level, BINTEST, text); case FILE_DEFAULT: /* nothing to check */ default: