diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-03-06 07:53:25 -1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-03-06 07:53:25 -1000 |
| commit | ebb0f38bb47f74b29e267babdbcd2c47d5292aa8 (patch) | |
| tree | 08d5de22ef643daece4769b36c32ceab024c92c8 | |
| parent | d810d4c27bf34c719243bab9feb0d843edc09fd7 (diff) | |
fs/pipe: fix pipe buffer index use in FUSE
This was another case that Rasmus pointed out where the direct access to
the pipe head and tail pointers broke on 32-bit configurations due to
the type changes.
As with the pipe FIONREAD case, fix it by using the appropriate helper
functions that deal with the right pipe index sizing.
Reported-by: Rasmus Villemoes <ravi@prevas.dk>
Link: https://lore.kernel.org/all/878qpi5wz4.fsf@prevas.dk/
Fixes: 3d252160b818 ("fs/pipe: Read pipe->{head,tail} atomically outside pipe->mutex")Cc: Oleg >
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Swapnil Sapkal <swapnil.sapkal@amd.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/fuse/dev.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index 2b2d1b755544..3c9caafca9e2 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -2107,7 +2107,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, struct file *out, loff_t *ppos, size_t len, unsigned int flags) { - unsigned int head, tail, mask, count; + unsigned int head, tail, count; unsigned nbuf; unsigned idx; struct pipe_buffer *bufs; @@ -2124,8 +2124,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, head = pipe->head; tail = pipe->tail; - mask = pipe->ring_size - 1; - count = head - tail; + count = pipe_occupancy(head, tail); bufs = kvmalloc_array(count, sizeof(struct pipe_buffer), GFP_KERNEL); if (!bufs) { @@ -2135,8 +2134,8 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, nbuf = 0; rem = 0; - for (idx = tail; idx != head && rem < len; idx++) - rem += pipe->bufs[idx & mask].len; + for (idx = tail; !pipe_empty(head, idx) && rem < len; idx++) + rem += pipe_buf(pipe, idx)->len; ret = -EINVAL; if (rem < len) @@ -2147,10 +2146,10 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, struct pipe_buffer *ibuf; struct pipe_buffer *obuf; - if (WARN_ON(nbuf >= count || tail == head)) + if (WARN_ON(nbuf >= count || pipe_empty(head, tail))) goto out_free; - ibuf = &pipe->bufs[tail & mask]; + ibuf = pipe_buf(pipe, tail); obuf = &bufs[nbuf]; if (rem >= ibuf->len) { |