test_firmware: fix the memory leak of the allocated firmware buffer
commit 48e15602 upstream. The following kernel memory leak was noticed after running tools/testing/selftests/firmware/fw_run_tests.sh: [root@pc-mtodorov firmware]# cat /sys/kernel/debug/kmemleak . . . unreferenced object 0xffff955389bc3400 (size 1024): comm "test_firmware-0", pid 5451, jiffies 4294944822 (age 65.652s) hex dump (first 32 bytes): 47 48 34 35 36 37 0a 00 00 00 00 00 00 00 00 00 GH4567.......... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff962f5dec>] slab_post_alloc_hook+0x8c/0x3c0 [<ffffffff962fcca4>] __kmem_cache_alloc_node+0x184/0x240 [<ffffffff962704de>] kmalloc_trace+0x2e/0xc0 [<ffffffff9665b42d>] test_fw_run_batch_request+0x9d/0x180 [<ffffffff95fd813b>] kthread+0x10b/0x140 [<ffffffff95e033e9>] ret_from_fork+0x29/0x50 unreferenced object 0xffff9553c334b400 (size 1024): comm "test_firmware-1", pid 5452, jiffies 4294944822 (age 65.652s) hex dump (first 32 bytes): 47 48 34 35 36 37 0a 00 00 00 00 00 00 00 00 00 GH4567.......... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff962f5dec>] slab_post_alloc_hook+0x8c/0x3c0 [<ffffffff962fcca4>] __kmem_cache_alloc_node+0x184/0x240 [<ffffffff962704de>] kmalloc_trace+0x2e/0xc0 [<ffffffff9665b42d>] test_fw_run_batch_request+0x9d/0x180 [<ffffffff95fd813b>] kthread+0x10b/0x140 [<ffffffff95e033e9>] ret_from_fork+0x29/0x50 unreferenced object 0xffff9553c334f000 (size 1024): comm "test_firmware-2", pid 5453, jiffies 4294944822 (age 65.652s) hex dump (first 32 bytes): 47 48 34 35 36 37 0a 00 00 00 00 00 00 00 00 00 GH4567.......... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff962f5dec>] slab_post_alloc_hook+0x8c/0x3c0 [<ffffffff962fcca4>] __kmem_cache_alloc_node+0x184/0x240 [<ffffffff962704de>] kmalloc_trace+0x2e/0xc0 [<ffffffff9665b42d>] test_fw_run_batch_request+0x9d/0x180 [<ffffffff95fd813b>] kthread+0x10b/0x140 [<ffffffff95e033e9>] ret_from_fork+0x29/0x50 unreferenced object 0xffff9553c3348400 (size 1024): comm "test_firmware-3", pid 5454, jiffies 4294944822 (age 65.652s) hex dump (first 32 bytes): 47 48 34 35 36 37 0a 00 00 00 00 00 00 00 00 00 GH4567.......... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff962f5dec>] slab_post_alloc_hook+0x8c/0x3c0 [<ffffffff962fcca4>] __kmem_cache_alloc_node+0x184/0x240 [<ffffffff962704de>] kmalloc_trace+0x2e/0xc0 [<ffffffff9665b42d>] test_fw_run_batch_request+0x9d/0x180 [<ffffffff95fd813b>] kthread+0x10b/0x140 [<ffffffff95e033e9>] ret_from_fork+0x29/0x50 [root@pc-mtodorov firmware]# Note that the size 1024 corresponds to the size of the test firmware buffer. The actual number of the buffers leaked is around 70-110, depending on the test run. The cause of the leak is the following: request_partial_firmware_into_buf() and request_firmware_into_buf() provided firmware buffer isn't released on release_firmware(), we have allocated it and we are responsible for deallocating it manually. This is introduced in a number of context where previously only release_firmware() was called, which was insufficient. Reported-by:Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr> Fixes: 7feebfa4 ("test_firmware: add support for request_firmware_into_buf") Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Carpenter <error27@gmail.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Russ Weight <russell.h.weight@intel.com> Cc: Tianfei zhang <tianfei.zhang@intel.com> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Zhengchao Shao <shaozhengchao@huawei.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: linux-kernel@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: Scott Branden <sbranden@broadcom.com> Cc: Luis R. Rodriguez <mcgrof@kernel.org> Cc: linux-kselftest@vger.kernel.org Cc: stable@vger.kernel.org # v5.4 Signed-off-by:
Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr> Link: https://lore.kernel.org/r/20230509084746.48259-3-mirsad.todorovac@alu.unizg.hr Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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eef67dfd
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