diff options
| -rw-r--r-- | usr/src/cmd/mdb/common/mdb/mdb_io.c | 42 |
1 files changed, 35 insertions, 7 deletions
diff --git a/usr/src/cmd/mdb/common/mdb/mdb_io.c b/usr/src/cmd/mdb/common/mdb/mdb_io.c index 988fc7aa71..6113dcfe01 100644 --- a/usr/src/cmd/mdb/common/mdb/mdb_io.c +++ b/usr/src/cmd/mdb/common/mdb/mdb_io.c @@ -26,6 +26,7 @@ /* * Copyright 2020 Joyent, Inc. * Copyright (c) 2016 by Delphix. All rights reserved. + * Copyright 2022 Oxide Computer Company */ /* @@ -847,7 +848,7 @@ static const char * iob_addr2str(uintptr_t addr) { static char buf[MDB_TGT_SYM_NAMLEN]; - char *name = buf; + size_t buflen = sizeof (buf); longlong_t offset; GElf_Sym sym; @@ -855,8 +856,27 @@ iob_addr2str(uintptr_t addr) MDB_TGT_SYM_FUZZY, buf, sizeof (buf), &sym, NULL) == -1) return (NULL); - if (mdb.m_demangler != NULL && (mdb.m_flags & MDB_FL_DEMANGLE)) - name = (char *)mdb_dem_convert(mdb.m_demangler, buf); + if (mdb.m_demangler != NULL && (mdb.m_flags & MDB_FL_DEMANGLE)) { + /* + * The mdb demangler attempts to either return us our original + * name or a pointer to something it has changed. If it has + * returned our original name, we want to update buf with that + * so we can later modify it. Unfortunately if we find we exceed + * the buffer, there's not an easy way to warn the user about + * this, so we just truncate the symbol with a '???' and return + * it. To someone finding this due to having seen that in a + * symbol, sorry. + */ + const char *dem = mdb_dem_convert(mdb.m_demangler, buf); + if (dem != buf) { + if (strlcpy(buf, dem, buflen) >= buflen) { + buf[buflen - 1] = '?'; + buf[buflen - 2] = '?'; + buf[buflen - 3] = '?'; + return (buf); + } + } + } /* * Here we provide a little cooperation between the %a formatting code @@ -868,17 +888,25 @@ iob_addr2str(uintptr_t addr) * query for us with a different address. We detect this case by * comparing the initial characters of buf to the special PLT= string. */ - if (sym.st_value != addr && strncmp(name, "PLT=", 4) != 0) { + if (sym.st_value != addr && strncmp(buf, "PLT=", 4) != 0) { if (sym.st_value > addr) offset = -(longlong_t)(sym.st_value - addr); else offset = (longlong_t)(addr - sym.st_value); - (void) strcat(name, numtostr(offset, mdb.m_radix, - NTOS_SIGNPOS | NTOS_SHOWBASE)); + /* + * See the earlier note in this function about how we handle + * demangler output for why we've dealt with things this way. + */ + if (strlcat(buf, numtostr(offset, mdb.m_radix, + NTOS_SIGNPOS | NTOS_SHOWBASE), buflen) >= buflen) { + buf[buflen - 1] = '?'; + buf[buflen - 2] = '?'; + buf[buflen - 3] = '?'; + } } - return (name); + return (buf); } /* |