On Mon, 19 Jun 2023, pan2...@intel.com wrote: > From: Pan Li <pan2...@intel.com> > > We extend the machine mode from 8 to 16 bits already. But there still > one placing missing from the tree-streamer. It has one hard coded array > for the machine code like size 256. > > In the lto pass, we memset the array by MAX_MACHINE_MODE count but the > value of the MAX_MACHINE_MODE will grow as more and more modes are added. > While the machine mode array in tree-streamer still leave 256 as is. > > Then, when the MAX_MACHINE_MODE is greater than 256, the memset of > lto_output_init_mode_table will touch the memory out of range unexpected. > > This patch would like to take the MAX_MACHINE_MODE as the size of the > array in tree-streamer, to make sure there is no potential unexpected > memory access in future.
Please review more careful: void lto_input_mode_table (struct lto_file_decl_data *file_data) { ... while ((m = bp_unpack_value (&bp, 8)) != VOIDmode) reads 8 bits again. ibit = bp_unpack_value (&bp, 8); fbit = bp_unpack_value (&bp, 8); likewise. Also file_data->mode_table is indexed by the _host_ mode, so you have to allocate enough space to fill in all streamed modes but you are using the targets MAX_MACHINE_MODE here. I think we need to stream the hosts MAX_MACHINE_MODE. Richard. > Signed-off-by: Pan Li <pan2...@intel.com> > > gcc/ChangeLog: > > * lto-streamer-in.cc (lto_input_mode_table): Use > MAX_MACHINE_MODE for memory allocation. > * tree-streamer.cc: Use MAX_MACHINE_MODE for array size. > * tree-streamer.h (streamer_mode_table): Ditto. > (bp_pack_machine_mode): Ditto. > (bp_unpack_machine_mode): Ditto. > --- > gcc/lto-streamer-in.cc | 3 ++- > gcc/tree-streamer.cc | 2 +- > gcc/tree-streamer.h | 7 ++++--- > 3 files changed, 7 insertions(+), 5 deletions(-) > > diff --git a/gcc/lto-streamer-in.cc b/gcc/lto-streamer-in.cc > index 2cb83406db5..102b7e18526 100644 > --- a/gcc/lto-streamer-in.cc > +++ b/gcc/lto-streamer-in.cc > @@ -1985,7 +1985,8 @@ lto_input_mode_table (struct lto_file_decl_data > *file_data) > internal_error ("cannot read LTO mode table from %s", > file_data->file_name); > > - unsigned char *table = ggc_cleared_vec_alloc<unsigned char> (1 << 8); > + unsigned char *table = ggc_cleared_vec_alloc<unsigned char> ( > + MAX_MACHINE_MODE); > file_data->mode_table = table; > const struct lto_simple_header_with_strings *header > = (const struct lto_simple_header_with_strings *) data; > diff --git a/gcc/tree-streamer.cc b/gcc/tree-streamer.cc > index ed65a7692e3..a28ef9c7920 100644 > --- a/gcc/tree-streamer.cc > +++ b/gcc/tree-streamer.cc > @@ -35,7 +35,7 @@ along with GCC; see the file COPYING3. If not see > During streaming in, we translate the on the disk mode using this > table. For normal LTO it is set to identity, for ACCEL_COMPILER > depending on the mode_table content. */ > -unsigned char streamer_mode_table[1 << 8]; > +unsigned char streamer_mode_table[MAX_MACHINE_MODE]; > > /* Check that all the TS_* structures handled by the streamer_write_* and > streamer_read_* routines are exactly ALL the structures defined in > diff --git a/gcc/tree-streamer.h b/gcc/tree-streamer.h > index 170d61cf20b..be3a1938e76 100644 > --- a/gcc/tree-streamer.h > +++ b/gcc/tree-streamer.h > @@ -75,7 +75,7 @@ void streamer_write_tree_body (struct output_block *, tree); > void streamer_write_integer_cst (struct output_block *, tree); > > /* In tree-streamer.cc. */ > -extern unsigned char streamer_mode_table[1 << 8]; > +extern unsigned char streamer_mode_table[MAX_MACHINE_MODE]; > void streamer_check_handled_ts_structures (void); > bool streamer_tree_cache_insert (struct streamer_tree_cache_d *, tree, > hashval_t, unsigned *); > @@ -108,7 +108,7 @@ inline void > bp_pack_machine_mode (struct bitpack_d *bp, machine_mode mode) > { > streamer_mode_table[mode] = 1; > - bp_pack_enum (bp, machine_mode, 1 << 8, mode); > + bp_pack_enum (bp, machine_mode, MAX_MACHINE_MODE, mode); > } > > inline machine_mode > @@ -116,7 +116,8 @@ bp_unpack_machine_mode (struct bitpack_d *bp) > { > return (machine_mode) > ((class lto_input_block *) > - bp->stream)->mode_table[bp_unpack_enum (bp, machine_mode, 1 << 8)]; > + bp->stream)->mode_table[bp_unpack_enum (bp, machine_mode, > + MAX_MACHINE_MODE)]; > } > > #endif /* GCC_TREE_STREAMER_H */ > -- Richard Biener <rguent...@suse.de> SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg, Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman; HRB 36809 (AG Nuernberg)