diff options
| author | Junrui Luo <moonafterrain@outlook.com> | 2026-06-17 15:09:17 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-07-04 13:38:41 +0200 |
| commit | d43afc412d439ffca1567e7ca8652be22f272b3b (patch) | |
| tree | ece4e42d45d5df381ac4c9c68941fa5a3afe0148 | |
| parent | 77fa80a1b7322e122122ce863a0b82d49cbd79c6 (diff) | |
| download | linux-d43afc412d439ffca1567e7ca8652be22f272b3b.tar.gz linux-d43afc412d439ffca1567e7ca8652be22f272b3b.zip | |
misc: fastrpc: fix DMA address corruption due to find_vma misuse
[ Upstream commit 464c6ad2aa16e1e1df9d559289199356493d1e00 ]
fastrpc_get_args() uses find_vma() to look up the VMA for a user-provided
pointer and compute a DMA address offset. When the address falls in a gap
before the returned VMA, (ptr & PAGE_MASK) - vma->vm_start underflows,
corrupting the DMA address sent to the DSP.
Replace find_vma() with vma_lookup(), which returns NULL when the address
is not contained within any VMA.
Cc: stable@vger.kernel.org
Fixes: 80f3afd72bd4 ("misc: fastrpc: consider address offset before sending to DSP")
Reported-by: Yuhao Jiang <danisjiang@gmail.com>
Signed-off-by: Junrui Luo <moonafterrain@outlook.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260530204528.116920-3-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ adapted `vma_lookup(mm, ptr)` to `find_vma(mm, ptr)` plus a `ptr >= vma->vm_start` guard since `vma_lookup()` does not exist in 5.10 ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/misc/fastrpc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c index f0d12fe34b85..e77c63467622 100644 --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -875,7 +875,7 @@ static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx) mmap_read_lock(current->mm); vma = find_vma(current->mm, ctx->args[i].ptr); - if (vma) + if (vma && ctx->args[i].ptr >= vma->vm_start) pages[i].addr += (ctx->args[i].ptr & PAGE_MASK) - vma->vm_start; mmap_read_unlock(current->mm); |