From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- tools/perf/util/zlib.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) create mode 100644 tools/perf/util/zlib.c (limited to 'tools/perf/util/zlib.c') diff --git a/tools/perf/util/zlib.c b/tools/perf/util/zlib.c new file mode 100644 index 000000000..1f7c06523 --- /dev/null +++ b/tools/perf/util/zlib.c @@ -0,0 +1,97 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "util/compress.h" + +#define CHUNK_SIZE 16384 + +int gzip_decompress_to_file(const char *input, int output_fd) +{ + int ret = Z_STREAM_ERROR; + int input_fd; + void *ptr; + int len; + struct stat stbuf; + unsigned char buf[CHUNK_SIZE]; + z_stream zs = { + .zalloc = Z_NULL, + .zfree = Z_NULL, + .opaque = Z_NULL, + .avail_in = 0, + .next_in = Z_NULL, + }; + + input_fd = open(input, O_RDONLY); + if (input_fd < 0) + return -1; + + if (fstat(input_fd, &stbuf) < 0) + goto out_close; + + ptr = mmap(NULL, stbuf.st_size, PROT_READ, MAP_PRIVATE, input_fd, 0); + if (ptr == MAP_FAILED) + goto out_close; + + if (inflateInit2(&zs, 16 + MAX_WBITS) != Z_OK) + goto out_unmap; + + zs.next_in = ptr; + zs.avail_in = stbuf.st_size; + + do { + zs.next_out = buf; + zs.avail_out = CHUNK_SIZE; + + ret = inflate(&zs, Z_NO_FLUSH); + switch (ret) { + case Z_NEED_DICT: + ret = Z_DATA_ERROR; + /* fall through */ + case Z_DATA_ERROR: + case Z_MEM_ERROR: + goto out; + default: + break; + } + + len = CHUNK_SIZE - zs.avail_out; + if (writen(output_fd, buf, len) != len) { + ret = Z_DATA_ERROR; + goto out; + } + + } while (ret != Z_STREAM_END); + +out: + inflateEnd(&zs); +out_unmap: + munmap(ptr, stbuf.st_size); +out_close: + close(input_fd); + + return ret == Z_STREAM_END ? 0 : -1; +} + +bool gzip_is_compressed(const char *input) +{ + int fd = open(input, O_RDONLY); + const uint8_t magic[2] = { 0x1f, 0x8b }; + char buf[2] = { 0 }; + ssize_t rc; + + if (fd < 0) + return false; + + rc = read(fd, buf, sizeof(buf)); + close(fd); + return rc == sizeof(buf) ? + memcmp(buf, magic, sizeof(buf)) == 0 : false; +} -- cgit v1.3.1