From: Alan Modra Date: Tue, 11 Apr 2023 12:41:26 +0000 (+0930) Subject: pe_ILF_object_p and bfd_check_format_matches X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=f656f9c77c27298c71f0c864d3e8a095a55cb594;p=binutils-gdb.git pe_ILF_object_p and bfd_check_format_matches If pe_ILF_object_p succeeds, pe_ILF_build_a_bfd will have changed the bfd from being file backed to in-memory. This can have unfortunate results for targets checked by bfd_check_format_matches after that point as they will be matching against the created in-memory image rather than the file. bfd_preserve_restore also has a problem if it flips the BFD_IN_MEMORY flag, because the flag affects iostream meaning and should be set if using _bfd_memory_iovec. To fix these problems, save and restore iostream and iovec along with flags, and modify bfd_reinit to make the bfd file backed again. Restoring the iovec and iostream allows the hack in bfd_reinit keeping BFD_IN_MEMORY (part of BFD_FLAGS_SAVED) to be removed. One more detail: If restoring from file backed to in-memory then the bfd needs to be forcibly removed from the cache lru list, since after the bfd becomes in-memory a bfd_close will delete the bfd's memory leaving the lru list pointing into freed memory. * cache.c (bfd_cache_init): Clear BFD_CLOSED_BY_CACHE here.. (bfd_cache_lookup_worker): ..rather than here. (bfd_cache_close): Comment. * format.c (struct bfd_preserve): Add iovec and iostream fields. (bfd_preserve_save): Save them.. (bfd_preserve_restore): ..and restore them, calling bfd_cache_close if the iovec differs. (bfd_reinit): Add preserve param. If the bfd has been flipped to in-memory, reopen the file. Restore flags. * peicode.h (pe_ILF_cleanup): New function. (pe_ILF_object_p): Return it. * bfd.c (BFD_FLAGS_SAVED): Delete. * bfd-in2.h: Regenerate. --- diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h index b60ff960f08..a04e97eda67 100644 --- a/bfd/bfd-in2.h +++ b/bfd/bfd-in2.h @@ -6622,12 +6622,6 @@ struct bfd /* Compress sections in this BFD with SHF_COMPRESSED zstd. */ #define BFD_COMPRESS_ZSTD 0x400000 - /* Flags bits to be saved in bfd_preserve_save. */ -#define BFD_FLAGS_SAVED \ - (BFD_IN_MEMORY | BFD_COMPRESS | BFD_DECOMPRESS | BFD_LINKER_CREATED \ - | BFD_PLUGIN | BFD_COMPRESS_GABI | BFD_CONVERT_ELF_COMMON \ - | BFD_USE_ELF_STT_COMMON | BFD_COMPRESS_ZSTD) - /* Flags bits which are for BFD use only. */ #define BFD_FLAGS_FOR_BFD_USE_MASK \ (BFD_IN_MEMORY | BFD_COMPRESS | BFD_DECOMPRESS | BFD_LINKER_CREATED \ diff --git a/bfd/bfd.c b/bfd/bfd.c index 3624bfbc9a5..650df1c79ed 100644 --- a/bfd/bfd.c +++ b/bfd/bfd.c @@ -181,12 +181,6 @@ CODE_FRAGMENT . {* Compress sections in this BFD with SHF_COMPRESSED zstd. *} .#define BFD_COMPRESS_ZSTD 0x400000 . -. {* Flags bits to be saved in bfd_preserve_save. *} -.#define BFD_FLAGS_SAVED \ -. (BFD_IN_MEMORY | BFD_COMPRESS | BFD_DECOMPRESS | BFD_LINKER_CREATED \ -. | BFD_PLUGIN | BFD_COMPRESS_GABI | BFD_CONVERT_ELF_COMMON \ -. | BFD_USE_ELF_STT_COMMON | BFD_COMPRESS_ZSTD) -. . {* Flags bits which are for BFD use only. *} .#define BFD_FLAGS_FOR_BFD_USE_MASK \ . (BFD_IN_MEMORY | BFD_COMPRESS | BFD_DECOMPRESS | BFD_LINKER_CREATED \ diff --git a/bfd/cache.c b/bfd/cache.c index ab36c8506bd..3b91cce2307 100644 --- a/bfd/cache.c +++ b/bfd/cache.c @@ -266,10 +266,7 @@ bfd_cache_lookup_worker (bfd *abfd, enum cache_flag flag) && !(flag & CACHE_NO_SEEK_ERROR)) bfd_set_error (bfd_error_system_call); else - { - abfd->flags &= ~BFD_CLOSED_BY_CACHE; - return (FILE *) abfd->iostream; - } + return (FILE *) abfd->iostream; /* xgettext:c-format */ _bfd_error_handler (_("reopening %pB: %s"), @@ -506,6 +503,7 @@ bfd_cache_init (bfd *abfd) } abfd->iovec = &cache_iovec; insert (abfd); + abfd->flags &= ~BFD_CLOSED_BY_CACHE; ++open_files; return true; } @@ -528,6 +526,7 @@ DESCRIPTION bool bfd_cache_close (bfd *abfd) { + /* Don't remove this test. bfd_reinit depends on it. */ if (abfd->iovec != &cache_iovec) return true; diff --git a/bfd/format.c b/bfd/format.c index 5ad4190d5c4..dd50b5e653a 100644 --- a/bfd/format.c +++ b/bfd/format.c @@ -99,6 +99,8 @@ struct bfd_preserve void *marker; void *tdata; flagword flags; + const struct bfd_iovec *iovec; + void *iostream; const struct bfd_arch_info *arch_info; struct bfd_section *sections; struct bfd_section *section_last; @@ -125,6 +127,8 @@ bfd_preserve_save (bfd *abfd, struct bfd_preserve *preserve, preserve->tdata = abfd->tdata.any; preserve->arch_info = abfd->arch_info; preserve->flags = abfd->flags; + preserve->iovec = abfd->iovec; + preserve->iostream = abfd->iostream; preserve->sections = abfd->sections; preserve->section_last = abfd->section_last; preserve->section_count = abfd->section_count; @@ -143,14 +147,24 @@ bfd_preserve_save (bfd *abfd, struct bfd_preserve *preserve, /* Clear out a subset of BFD state. */ static void -bfd_reinit (bfd *abfd, unsigned int section_id, bfd_cleanup cleanup) +bfd_reinit (bfd *abfd, unsigned int section_id, + struct bfd_preserve *preserve, bfd_cleanup cleanup) { _bfd_section_id = section_id; if (cleanup) cleanup (abfd); abfd->tdata.any = NULL; abfd->arch_info = &bfd_default_arch_struct; - abfd->flags &= BFD_FLAGS_SAVED; + if ((abfd->flags & BFD_CLOSED_BY_CACHE) != 0 + && (abfd->flags & BFD_IN_MEMORY) != 0 + && (preserve->flags & BFD_CLOSED_BY_CACHE) == 0 + && (preserve->flags & BFD_IN_MEMORY) == 0) + { + /* This is to reverse pe_ILF_build_a_bfd, which closes the file + and sets up a bfd in memory. */ + bfd_open_file (abfd); + } + abfd->flags = preserve->flags; abfd->build_id = NULL; bfd_section_list_clear (abfd); } @@ -164,7 +178,11 @@ bfd_preserve_restore (bfd *abfd, struct bfd_preserve *preserve) abfd->tdata.any = preserve->tdata; abfd->arch_info = preserve->arch_info; + if (abfd->iovec != preserve->iovec) + bfd_cache_close (abfd); abfd->flags = preserve->flags; + abfd->iovec = preserve->iovec; + abfd->iostream = preserve->iostream; abfd->section_htab = preserve->section_htab; abfd->sections = preserve->sections; abfd->section_last = preserve->section_last; @@ -368,7 +386,7 @@ bfd_check_format_matches (bfd *abfd, bfd_format format, char ***matching) /* If we already tried a match, the bfd is modified and may have sections attached, which will confuse the next _bfd_check_format call. */ - bfd_reinit (abfd, initial_section_id, cleanup); + bfd_reinit (abfd, initial_section_id, &preserve, cleanup); /* Free bfd_alloc memory too. If we have matched and preserved a target then the high water mark is that much higher. */ if (preserve_match.marker) @@ -527,7 +545,7 @@ bfd_check_format_matches (bfd *abfd, bfd_format format, char ***matching) RIGHT_TARG again. */ if (match_targ != right_targ) { - bfd_reinit (abfd, initial_section_id, cleanup); + bfd_reinit (abfd, initial_section_id, &preserve, cleanup); bfd_release (abfd, preserve.marker); if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0) goto err_ret; diff --git a/bfd/peicode.h b/bfd/peicode.h index f16aeca7a1b..e2e2be65b5d 100644 --- a/bfd/peicode.h +++ b/bfd/peicode.h @@ -1158,6 +1158,17 @@ pe_ILF_build_a_bfd (bfd * abfd, return false; } +/* Cleanup function, returned from check_format hook. */ + +static void +pe_ILF_cleanup (bfd *abfd) +{ + struct bfd_in_memory *bim = abfd->iostream; + free (bim->buffer); + free (bim); + abfd->iostream = NULL; +} + /* We have detected an Import Library Format archive element. Decode the element and return the appropriate target. */ @@ -1331,7 +1342,7 @@ pe_ILF_object_p (bfd * abfd) return NULL; } - return _bfd_no_cleanup; + return pe_ILF_cleanup; } static void