diff options
| author | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2023-06-09 15:26:25 -0400 |
|---|---|---|
| committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2023-08-23 15:58:47 -0400 |
| commit | 303a78052091c81e9003915c521fdca1c7e117af (patch) | |
| tree | 2616e0e3ddc48fee94929cf7e1220013b0e2377f /fs/nfs/nfs42xdr.c | |
| parent | 8d18f6c5bb864d97a730f471c56cdecf313efe64 (diff) | |
| download | lwn-303a78052091c81e9003915c521fdca1c7e117af.tar.gz lwn-303a78052091c81e9003915c521fdca1c7e117af.zip | |
NFSv4.2: Rework scratch handling for READ_PLUS (again)
I found that the read code might send multiple requests using the same
nfs_pgio_header, but nfs4_proc_read_setup() is only called once. This is
how we ended up occasionally double-freeing the scratch buffer, but also
means we set a NULL pointer but non-zero length to the xdr scratch
buffer. This results in an oops the first time decoding needs to copy
something to scratch, which frequently happens when decoding READ_PLUS
hole segments.
I fix this by moving scratch handling into the pageio read code. I
provide a function to allocate scratch space for decoding read replies,
and free the scratch buffer when the nfs_pgio_header is freed.
Fixes: fbd2a05f29a9 (NFSv4.2: Rework scratch handling for READ_PLUS)
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'fs/nfs/nfs42xdr.c')
| -rw-r--r-- | fs/nfs/nfs42xdr.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c index 78193f04d892..9e3ae53e2205 100644 --- a/fs/nfs/nfs42xdr.c +++ b/fs/nfs/nfs42xdr.c @@ -1433,7 +1433,7 @@ static int nfs4_xdr_dec_read_plus(struct rpc_rqst *rqstp, struct compound_hdr hdr; int status; - xdr_set_scratch_buffer(xdr, res->scratch, sizeof(res->scratch)); + xdr_set_scratch_buffer(xdr, res->scratch, READ_PLUS_SCRATCH_SIZE); status = decode_compound_hdr(xdr, &hdr); if (status) |