On 3/28/22 12:40, Damien Le Moal wrote: > On 3/28/22 12:26, cgel.zte@xxxxxxxxx wrote: >> From: Lv Ruyi <lv.ruyi@xxxxxxxxxx> >> >> kmem_zalloc() is a memory allocation function which can return NULL when >> some internal memory errors happen. It is safer to check NULL pointer. >> >> Reported-by: Zeal Robot <zealci@xxxxxxxxxx> >> Signed-off-by: Lv Ruyi <lv.ruyi@xxxxxxxxxx> >> --- >> fs/xfs/libxfs/xfs_attr_leaf.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c >> index 014daa8c542d..e6694f49f563 100644 >> --- a/fs/xfs/libxfs/xfs_attr_leaf.c >> +++ b/fs/xfs/libxfs/xfs_attr_leaf.c >> @@ -1571,6 +1571,8 @@ xfs_attr3_leaf_compact( >> trace_xfs_attr_leaf_compact(args); >> >> tmpbuffer = kmem_alloc(args->geo->blksize, 0); > > See kmem_alloc() code: this function cannot fail (it retries the > allocation until success). So checking for NULL pointer does not make sense. Note: this comment is not 100% correct. kmem_alloc() can fail if KM_MAYFAIL is specified as a flag. But that is not the case here. > >> + if (!tmpbuffer) >> + return; >> memcpy(tmpbuffer, bp->b_addr, args->geo->blksize); >> memset(bp->b_addr, 0, args->geo->blksize); >> leaf_src = (xfs_attr_leafblock_t *)tmpbuffer; >> @@ -2290,6 +2292,8 @@ xfs_attr3_leaf_unbalance( >> struct xfs_attr3_icleaf_hdr tmphdr; >> >> tmp_leaf = kmem_zalloc(state->args->geo->blksize, 0); >> + if (!tmp_leaf) >> + return; >> >> /* >> * Copy the header into the temp leaf so that all the stuff > > -- Damien Le Moal Western Digital Research
