In message <4be9102c.6040...@axio.ms> you wrote: > > add_dyn_reconf_usable_mem_property() iterates over memory spans > in /ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory and intersects > these with usablemem_rgns ranges. Not only did it seem to write > null properties for every range that didn't match, but it used an unchecked > fixed-size array which will overrun on machines with lots of LMBs. > > This patch stops add_dyn_reconf_usable_mem_property() from adding null ranges > to the linux,drconf-usable-memory property and removes its fixed-size array, > as well as the array in add_usable_mem_property, in lieu of malloc/realloc/fr ee. >
Thanks matt! Acked-by: Michael Neuling <mi...@neuling.org> > Signed-off-by: Matt Evans <m...@ozlabs.org> > --- > kexec/arch/ppc64/fs2dt.c | 66 +++++++++++++++++++++++++++++++++++++------- - > 1 files changed, 54 insertions(+), 12 deletions(-) > > diff --git a/kexec/arch/ppc64/fs2dt.c b/kexec/arch/ppc64/fs2dt.c > index 762bf04..7470132 100644 > --- a/kexec/arch/ppc64/fs2dt.c > +++ b/kexec/arch/ppc64/fs2dt.c > @@ -37,7 +37,7 @@ > #define NAMESPACE 16384 /* max bytes for property names */ > #define INIT_TREE_WORDS 65536 /* Initial num words for prop values */ > #define MEMRESERVE 256 /* max number of reserved memory blocks */ > -#define MAX_MEMORY_RANGES 1024 > +#define MEM_RANGE_CHUNK_SZ 2048 /* Initial num dwords for mem ranges */ > > static char pathname[MAXPATH], *pathstart; > static char propnames[NAMESPACE] = { 0 }; > @@ -148,7 +148,8 @@ static void add_dyn_reconf_usable_mem_property(int fd) > { > char fname[MAXPATH], *bname; > uint64_t buf[32]; > - uint64_t ranges[2*MAX_MEMORY_RANGES]; > + uint64_t *ranges; > + int ranges_size = MEM_RANGE_CHUNK_SZ; > uint64_t base, end, loc_base, loc_end; > size_t i, rngs_cnt, range; > int rlen = 0; > @@ -165,6 +166,11 @@ static void add_dyn_reconf_usable_mem_property(int fd) > die("unrecoverable error: error seeking in \"%s\": %s\n", > pathname, strerror(errno)); > > + ranges = malloc(ranges_size*8); > + if (!ranges) > + die("unrecoverable error: can't alloc %d bytes for ranges.\n", > + ranges_size*8); > + > rlen = 0; > for (i = 0; i < num_of_lmbs; i++) { > if (read(fd, buf, 24) < 0) > @@ -180,24 +186,41 @@ static void add_dyn_reconf_usable_mem_property(int fd) > > rngs_cnt = 0; > for (range = 0; range < usablemem_rgns.size; range++) { > + int add = 0; > loc_base = usablemem_rgns.ranges[range].start; > loc_end = usablemem_rgns.ranges[range].end; > if (loc_base >= base && loc_end <= end) { > - ranges[rlen++] = loc_base; > - ranges[rlen++] = loc_end - loc_base; > - rngs_cnt++; > + add = 1; > } else if (base < loc_end && end > loc_base) { > if (loc_base < base) > loc_base = base; > if (loc_end > end) > loc_end = end; > + add = 1; > + } > + > + if (add) { > + if (rlen >= (ranges_size-2)) { > + ranges_size += MEM_RANGE_CHUNK_SZ; > + ranges = realloc(ranges, ranges_size*8) ; > + if (!ranges) > + die("unrecoverable error: can't " > + " realloc %d bytes for" > + " ranges.\n", > + ranges_size*8); > + } > ranges[rlen++] = loc_base; > ranges[rlen++] = loc_end - loc_base; > rngs_cnt++; > } > } > - /* Store the count of (base, size) duple */ > - ranges[tmp_indx] = rngs_cnt; > + if (rngs_cnt == 0) { > + /* Don't store anything for unwritten iterations! */ > + rlen = tmp_indx; > + } else { > + /* Store the count of (base, size) duple */ > + ranges[tmp_indx] = rngs_cnt; > + } > } > > rlen = rlen * sizeof(uint64_t); > @@ -210,7 +233,8 @@ static void add_dyn_reconf_usable_mem_property(int fd) > *dt++ = propnum("linux,drconf-usable-memory"); > if ((rlen >= 8) && ((unsigned long)dt & 0x4)) > dt++; > - memcpy(dt, &ranges, rlen); > + memcpy(dt, ranges, rlen); > + free(ranges); > dt += (rlen + 3)/4; > } > > @@ -218,7 +242,8 @@ static void add_usable_mem_property(int fd, size_t len) > { > char fname[MAXPATH], *bname; > uint64_t buf[2]; > - uint64_t ranges[2*MAX_MEMORY_RANGES]; > + uint64_t *ranges; > + int ranges_size = MEM_RANGE_CHUNK_SZ; > uint64_t base, end, loc_base, loc_end; > size_t range; > int rlen = 0; > @@ -247,17 +272,33 @@ static void add_usable_mem_property(int fd, size_t len) > base = buf[0]; > end = base + buf[1]; > > + ranges = malloc(ranges_size*8); > + if (!ranges) > + die("unrecoverable error: can't alloc %d bytes for ranges.\n", > + ranges_size*8); > + > for (range = 0; range < usablemem_rgns.size; range++) { > + int add = 0; > loc_base = usablemem_rgns.ranges[range].start; > loc_end = usablemem_rgns.ranges[range].end; > if (loc_base >= base && loc_end <= end) { > - ranges[rlen++] = loc_base; > - ranges[rlen++] = loc_end - loc_base; > + add = 1; > } else if (base < loc_end && end > loc_base) { > if (loc_base < base) > loc_base = base; > if (loc_end > end) > loc_end = end; > + add = 1; > + } > + if (add) { > + if (rlen >= (ranges_size-2)) { > + ranges_size += MEM_RANGE_CHUNK_SZ; > + ranges = realloc(ranges, ranges_size*8); > + if (!ranges) > + die("unrecoverable error: can't realloc " > + "%d bytes for ranges.\n", > + ranges_size*8); > + } > ranges[rlen++] = loc_base; > ranges[rlen++] = loc_end - loc_base; > } > @@ -283,7 +324,8 @@ static void add_usable_mem_property(int fd, size_t len) > *dt++ = propnum("linux,usable-memory"); > if ((rlen >= 8) && ((unsigned long)dt & 0x4)) > dt++; > - memcpy(dt,&ranges,rlen); > + memcpy(dt, ranges, rlen); > + free(ranges); > dt += (rlen + 3)/4; > } > > -- > 1.6.3.3 > > > _______________________________________________ > kexec mailing list > ke...@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec > _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev