On Mon, 2018-05-28 at 16:37 +0000, Christophe Leroy wrote: > CC arch/powerpc/kernel/nvram_64.o > arch/powerpc/kernel/nvram_64.c: In function 'nvram_create_partition': > arch/powerpc/kernel/nvram_64.c:1042:2: error: 'strncpy' specified bound 12 > equals destination size [-Werror=stringop-truncation] > strncpy(new_part->header.name, name, 12); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > CC arch/powerpc/kernel/trace/ftrace.o > In function 'make_field', > inlined from 'ps3_repository_read_boot_dat_address' at > arch/powerpc/platforms/ps3/repository.c:900:9: > arch/powerpc/platforms/ps3/repository.c:106:2: error: 'strncpy' output > truncated before terminating nul copying 8 bytes from a string of the same > length [-Werror=stringop-truncation] > strncpy((char *)&n, text, 8); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
That's not completely correct, here it's gcc warning being over- zealous. The old specs I could find define the format to be a 12 characters strings *or* a less-than-12 characters NUL terminated string. So it's perfectly ok to drop the trailing 0 if the name happens to be exactly 12 characters. Cheers, Ben. > Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> > --- > arch/powerpc/kernel/nvram_64.c | 2 +- > arch/powerpc/platforms/ps3/repository.c | 4 ++-- > 2 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c > index ba681dac7b46..7507448cd904 100644 > --- a/arch/powerpc/kernel/nvram_64.c > +++ b/arch/powerpc/kernel/nvram_64.c > @@ -1039,7 +1039,7 @@ loff_t __init nvram_create_partition(const char *name, > int sig, > new_part->index = free_part->index; > new_part->header.signature = sig; > new_part->header.length = size; > - strncpy(new_part->header.name, name, 12); > + strncpy(new_part->header.name, name, sizeof(new_part->header.name) - 1); > new_part->header.checksum = nvram_checksum(&new_part->header); > > rc = nvram_write_header(new_part); > diff --git a/arch/powerpc/platforms/ps3/repository.c > b/arch/powerpc/platforms/ps3/repository.c > index 50dbaf24b1ee..b4d6628eec5e 100644 > --- a/arch/powerpc/platforms/ps3/repository.c > +++ b/arch/powerpc/platforms/ps3/repository.c > @@ -101,9 +101,9 @@ static u64 make_first_field(const char *text, u64 index) > > static u64 make_field(const char *text, u64 index) > { > - u64 n; > + u64 n = 0; > > - strncpy((char *)&n, text, 8); > + memcpy((char *)&n, text, min(sizeof(n), strlen(text))); > return n + index; > } >