In the Linux kernel, the following vulnerability has been resolved: module: decompress: check return value of module_extend_max_pages() module_extend_max_pages() calls kvrealloc() internally and returns -ENOMEM on allocation failure. The return value is never checked. If the initial allocation fails, info->pages remains NULL and info->max_pages remains 0. Subsequent calls to module_get_next_page() will attempt to dynamically grow the array by calling module_extend_max_pages(info, 0) since info->used_pages is 0. This results in kvrealloc(NULL, 0) returning ZERO_SIZE_PTR, which is treated as a success, leading to a dereference of ZERO_SIZE_PTR and a kernel oops. Fix: add the missing error check after module_extend_max_pages() and return immediately on failure. This matches the pattern used by every other kvrealloc() caller in the module loading path. [Sami: Corrected the analysis in the commit message.]

A flaw was found in the Linux kernel. An unchecked return value in the `module_extend_max_pages()` function within the module decompression logic can lead to a null pointer dereference. This vulnerability can be triggered if memory allocation fails during module loading, resulting in a kernel oops. This can allow a local attacker to cause a denial of service (DoS) by crashing the system.

In the Linux kernel, the following vulnerability has been resolved: module: decompress: check return value of module_extend_max_pages() module_extend_max_pages() calls kvrealloc() internally and returns -ENOMEM on allocation failure. The return value is never checked. If the initial allocation fails, info->pages remains NULL and info->max_pages remains 0. Subsequent calls to module_get_next_page() will attempt to dynamically grow the array by calling module_extend_max_pages(info, 0) since info->used_pages is 0. This results in kvrealloc(NULL, 0) returning ZERO_SIZE_PTR, which is treated as a success, leading to a dereference of ZERO_SIZE_PTR and a kernel oops. Fix: add the missing error check after module_extend_max_pages() and return immediately on failure. This matches the pattern used by every other kvrealloc() caller in the module loading path. [Sami: Corrected the analysis in the commit message.]

module: decompress: check return value of module_extend_max_pages()

In the Linux kernel, the following vulnerability has been resolved: m ...

In the Linux kernel, the following vulnerability has been resolved: module: decompress: check return value of module_extend_max_pages() module_extend_max_pages() calls kvrealloc() internally and returns -ENOMEM on allocation failure. The return value is never checked. If the initial allocation fails, info->pages remains NULL and info->max_pages remains 0. Subsequent calls to module_get_next_page() will attempt to dynamically grow the array by calling module_extend_max_pages(info, 0) since info->used_pages is 0. This results in kvrealloc(NULL, 0) returning ZERO_SIZE_PTR, which is treated as a success, leading to a dereference of ZERO_SIZE_PTR and a kernel oops. Fix: add the missing error check after module_extend_max_pages() and return immediately on failure. This matches the pattern used by every other kvrealloc() caller in the module loading path. [Sami: Corrected the analysis in the commit message.]