| Message ID | 20180202145952.285505-1-arnd@arndb.de |
|---|---|
| State | Accepted |
| Commit | 2cf2f0d5b91fd1b06a6ae260462fc7945ea84add |
| Headers | show |
| Series | kdb: use memmove instead of overlapping memcpy | expand |
On 02/02/2018 08:59 AM, Arnd Bergmann wrote: > gcc discovered that the memcpy() arguments in kdbnearsym() overlap, so > we should really use memmove(), which is defined to handle that correctly: > > In function 'memcpy', > inlined from 'kdbnearsym' at /git/arm-soc/kernel/debug/kdb/kdb_support.c:132:4: > /git/arm-soc/include/linux/string.h:353:9: error: '__builtin_memcpy' accessing 792 bytes at offsets 0 and 8 overlaps 784 bytes at offset 8 [-Werror=restrict] > return __builtin_memcpy(p, q, size); > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > kernel/debug/kdb/kdb_support.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c > index 5d8ef3a07ecd..1ad4370ccbf0 100644 > --- a/kernel/debug/kdb/kdb_support.c > +++ b/kernel/debug/kdb/kdb_support.c > @@ -129,13 +129,13 @@ int kdbnearsym(unsigned long addr, kdb_symtab_t *symtab) > } > if (i >= ARRAY_SIZE(kdb_name_table)) { > debug_kfree(kdb_name_table[0]); > - memcpy(kdb_name_table, kdb_name_table+1, > + memmove(kdb_name_table, kdb_name_table+1, > sizeof(kdb_name_table[0]) * > (ARRAY_SIZE(kdb_name_table)-1)); > } else { > debug_kfree(knt1); > knt1 = kdb_name_table[i]; > - memcpy(kdb_name_table+i, kdb_name_table+i+1, > + memmove(kdb_name_table+i, kdb_name_table+i+1, > sizeof(kdb_name_table[0]) * > (ARRAY_SIZE(kdb_name_table)-i-1)); > } > That is good by me. Many thanks! Added to queue. Reviewed-by: Jason Wessel <jason.wessel@windriver.com> Jason.
diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c index 5d8ef3a07ecd..1ad4370ccbf0 100644 --- a/kernel/debug/kdb/kdb_support.c +++ b/kernel/debug/kdb/kdb_support.c @@ -129,13 +129,13 @@ int kdbnearsym(unsigned long addr, kdb_symtab_t *symtab) } if (i >= ARRAY_SIZE(kdb_name_table)) { debug_kfree(kdb_name_table[0]); - memcpy(kdb_name_table, kdb_name_table+1, + memmove(kdb_name_table, kdb_name_table+1, sizeof(kdb_name_table[0]) * (ARRAY_SIZE(kdb_name_table)-1)); } else { debug_kfree(knt1); knt1 = kdb_name_table[i]; - memcpy(kdb_name_table+i, kdb_name_table+i+1, + memmove(kdb_name_table+i, kdb_name_table+i+1, sizeof(kdb_name_table[0]) * (ARRAY_SIZE(kdb_name_table)-i-1)); }
gcc discovered that the memcpy() arguments in kdbnearsym() overlap, so we should really use memmove(), which is defined to handle that correctly: In function 'memcpy', inlined from 'kdbnearsym' at /git/arm-soc/kernel/debug/kdb/kdb_support.c:132:4: /git/arm-soc/include/linux/string.h:353:9: error: '__builtin_memcpy' accessing 792 bytes at offsets 0 and 8 overlaps 784 bytes at offset 8 [-Werror=restrict] return __builtin_memcpy(p, q, size); Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- kernel/debug/kdb/kdb_support.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 2.9.0